This article is from the archive of our partner National Journal

Three weeks before Election Day, Republicans are on the brink of winning the Senate. But their advantage is so slight that a morale-sapping defeat is still very much possible.

That's the state of play in the latest edition of National Journal Hotline's Senate race rankings. At this point, it looks like Republicans have the inside track on taking over six red states currently represented by Democrats, and two of this year's rock-star GOP nominees also have Democrats on the ropes in a pair of swing states, Iowa and Colorado. Those states could give Republicans some breathing room if a state such as Alaska surprises when the returns come in. But late-breaking trouble in Kansas, of all places, has opened the door to continued Democratic control a little bit wider.

Democrats currently control 55 seats in the Senate, meaning the GOP has to win six to take over the chamber. As we've said before, the best way to think about the Senate landscape is in tiers: The top three states look very likely to flip; the GOP appears to have smaller advantages in the next three states; the next bloc of three look like something close to pure toss-ups; and the incumbent party is favored in the races after No. 9. The races in our list are ordered by the likelihood of the seat flipping between the parties.

1. Montana (Open D, Sen. John Walsh retiring) (Previous ranking: 3)

Montana Democrats are on their third candidate of the cycle at this point (fourth, if you count Brian Schweitzer's planned-then-canceled bid) after Walsh withdrew following graduate-school plagiarism revelations. That, in a nutshell, shows why the state has been the Democrats worst Senate race of 2014. It's almost hard to remember that last year, most analysts believed either Sen. Max Baucus or the former Gov. Schweitzer would hold the seat for their party. Now, GOP Rep. Steve Daines is nearly certain to win against Democratic state Rep. Amanda Curtis, which will mark the first time a Republican will hold the seat in more than 100 years.

2. West Virginia (Open D, Sen. Jay Rockefeller retiring) (Previous: 2)

Democratic Secretary of State Natalie Tennant hasn't done badly at all in this race, but GOP Rep. Shelley Moore Capito is just too strong and the state too conservative. This race has never really been on the radar, despite some late July spending by Senate Majority PAC—which just happened, coincidentally we're sure, to almost match the $250,000 Rockefeller donated to the Democratic super PAC this year.

3. South Dakota (Open D, Sen. Tim Johnson retiring) (Previous: 1)

Almost overnight, this race has risen from the dead. Make no mistake: Former GOP Gov. Mike Rounds is still the favorite here. But a coalition of outside groups has been hammering Rounds on his involvement in a visa scandal, and the Democratic Senatorial Campaign Committee said its internal polls showed a close-enough race to prompt a late $1 million TV blitz that started this week. The National Republican Senatorial Committee is responding with $1 million of its own. But with Rounds, Democrat Rick Weiland, and former Sen. Larry Pressler—a former Republican-turned-Obama-praising independent—splitting votes, each side faces a puzzling question of where to direct its firepower. While Rounds still solidly holds control of this race, Republicans are lamenting a lack of effort from what should have been a sure-thing campaign, forcing them to spend money in an unexpected place while other races around the country remain tightly contested.

4. Louisiana (D, Sen. Mary Landrieu) (Previous: 4)

The last few months have dulled some of the shine on Landrieu's vaunted political operation. First were a series of damaging stories about billing taxpayers for private plane rides, followed by news that her campaign manager was being replaced just a month before Election Day. Both have increased the palpable sense that the Bayou State's three-term senator is an underdog in her fight against GOP Rep. Bill Cassidy. Polls show the Republican physician, whose own campaign hasn't blown anyone away, with a slight edge on Landrieu. Still, this race is headed to a Dec. 6 runoff, and it's impossible to predict what that one-month contest will look like. (For example, whether the Senate majority is still at stake would have a major effect on the campaign.)

5. Arkansas (D, Sen. Mark Pryor) (Previous: 6)

This race is swinging back the way Republicans had always planned, a battle that has less to do with two-term Sen. Pryor's personal qualities and everything to do with an unpopular national Democratic agenda. Considering how inhospitable the state has become, Pryor may actually be exceeding expectations by keeping the race within a few points all summer. The Democrat has done everything he can to paint conservative superstar Tom Cotton as out of step with Arkansas. But Cotton's military background has come in handy as voters' attention shifted to foreign policy late this year.

(RELATED: The Hotline's House Race Rankings: The 30 Districts Most Likely to Change Hands in November)

6. Alaska (D, Sen. Mark Begich) (Previous: 7)

At the end of the summer, Begich had Alaska Republicans positively alarmed. The incumbent was running possibly the best Senate campaign in the country, the GOP primary was dragging on, and Begich's backup from outside groups was compounding Republican Dan Sullivan's problems. But things changed pretty quickly once Sullivan locked up the nomination. Begich is still running a formidable campaign (though he caught serious criticism for an ad that used a murder and sexual assault case from Sullivan's time as state attorney general despite complaints from the victims' lawyer), but the polls haven't been kind to him since then—last week, the first independent live-caller polls in Alaska this year both gave Sullivan small leads. But the race isn't over, even though Sullivan appears to have the upper hand right now. Not only is polling notoriously difficult in the state, Begich has constructed an unrivaled field program stretching far into remote rural areas that could boost Alaska Native turnout.

7. Iowa (Open D, Sen. Tom Harkin retiring) (Previous: 8)

It says a lot about this race that the Bloomberg/Des Moines Register poll that showed Democrat Bruce Braley in a statistical dead heat with Republican Joni Ernst (he trailed by one point, 47 percent to 46 percent) counts as good news for Democrats. Previous surveys painted a much more pessimistic picture for the congressman. Ernst shares some flaws that have proven fatal to past GOP Senate campaigns— her suggestion that privatizing Social Security is an "option," for instance, might have been the best thing to happen to Braley in months. But the state senator has also turned one of her early weaknesses into a huge strength, collecting an incredible $6 million in the last quarter after struggling to raise money at the beginning of her campaign. This is a race where both candidates have flaws—and whoever's flaws voters judge to be worse will lose what is one of the year's tightest contests.

8. Kansas (R, Sen. Pat Roberts) (Previous: Not Ranked)

New to our list, this race is perhaps the most perplexing, because a loss by Roberts doesn't necessarily place a win in either party's column. Independent Greg Orman, who now goes head-to-head with Roberts following Democrat Chad Taylor's withdrawal from the ballot, has not said which side he would join in the Senate if elected—only that he'd likely go with whoever had the majority. Republicans have sent in a new campaign team to overhaul Roberts's sleepy operation, and GOP-aligned outside groups have slowly but surely come to his aid against the wealthy Orman, attacking the independent's business records and Democratic connections. Roberts's biggest problem remains damage sustained in his difficult primary campaign; the polls that have shown him still viewed negatively have him trailing badly, while he was at least tied in recent ones where respondents viewed him more neutrally. But, if Roberts and friends can define Orman quickly and give voters pause about the political newcomer, Roberts still stands a good chance of righting the ship.

9. Colorado (D, Sen. Mark Udall) (Previous: 9)

Just because this race stayed in the same place on the list doesn't mean nothing changed. Republican hopes in both Iowa and Colorado have been rising for months now, and Cory Gardner moved into the lead in public polls and Republican internals. Democrats say they think the race is a dead-even heat right now, and what's more, they think that makes Udall a favorite, thanks to the party's vaunted ground game in the Rocky Mountain State. That will have a slightly different twist this year, the first time that every active voter will receive a mail ballot from the state. The Denver Post, the state's largest newspaper, rolled out its endorsement of Gardner over the weekend just before voting is set to start. Udall's campaign focus on birth control and contraception has helped open a big gender gap in the race, but the Post and others say he hasn't paid enough attention to other issues.

10. North Carolina (D, Sen. Kay Hagan) (Previous: 5)

Not many would have picked Kay Hagan to be the Democrats' strongest red-state incumbent when the cycle began, or, for that matter, after a winter spending barrage from Americans for Prosperity sent her poll numbers tumbling. But the first-term senator, once lightly regarded, has clawed her way back to a small advantage in recent polls, thanks in part to a spending binge from her own campaign and allies. GOP nominee Thom Tillis even trails in his campaign's own internal survey. The Tar Heel State has become the capital of the gender gap in 2014: Even as surveys show Tillis winning men by wavelike proportions, Hagan's advantage among women has canceled that out. Now, Hagan has to prove that the revelation she skipped an Armed Services Committee hearing for a fundraiser won't knock her off stride, though it certainly put her on the defensive in last week's final debate. And she has to hope that the Libertarian candidate, pizza deliveryman Sean Haugh, doesn't bleed all of his support to Tillis between now and Election Day.

11. New Hampshire (D, Sen. Jeanne Shaheen) (Previous: 13)

Scott Brown has closed the gap, but can he finish the job? The Republican transplant from Massachusetts still trails Shaheen in most polls, though he's done well enough to attract a seven-figure investment in the race from American Crossroads. Brown's biggest impediment at this point, after heavy advertising against him from Democrats, may be that while Shaheen remains popular, more people say they dislike him than like him in poll after poll. (Many more, in the case of the most recent WMUR poll, though CNN found a smaller spread.) Even in a state like New Hampshire that tends to feel national political trends strongly, that's not a good foundation for progress.

12. Georgia (Open R, Sen. Saxby Chambliss retiring) (Previous: 11)

This race was always going to be tough for former nonprofit CEO Michelle Nunn, especially when Republicans rejected three current lawmaker candidates in their primary, making a planned insider-versus-outsider campaign more difficult. Since then, both candidates have suffered some of the most notable opposition hits of the election cycle: a leaked Nunn campaign memo that detailed her own weaknesses and David Perdue's embrace of outsourcing in a deposition, which played right into one of Nunn's main lines of attack. Republican outside groups' reluctance to spend here defending a Republican seat has played in Nunn's favor, but the NRSC is coming to town for the last few weeks. Even Nunn's strong fundraising may not be enough to defend her in this red state, though it's changing enough that she might be able to force Perdue into a January runoff by holding him under 50 percent of the vote in November.

13. Kentucky (R, Sen. Mitch McConnell) (Previous: 10)

Democratic pollster Mark Mellman was on an island through much of the early fall when his internal surveys showed Democratic client Alison Lundergan Grimes leading Republican incumbent McConnell. And then the state's automated Bluegrass Poll showed the Democrat up 2 points, 46 percent to 44 percent. McConnell's campaign quickly pointed out, correctly, that the survey was an outlier, but it still suggested Grimes's campaign wasn't dead and buried yet (despite calls from some local Democrats to shake up her organization and a string of painful-to-watch encounters with reporters). But don't get us wrong: McConnell is still the strong favorite in this race, and it would take an immense anti-incumbent wave against the Senate minority leader for that to change.

14. Michigan (Open D, Sen. Carl Levin retiring) (Previous: 12)

This is possibly the one state in the country where Democrats have been on a consistent upward trajectory all year long. Despite a lot of spending to beat down Democratic Rep. Gary Peters and raise up Republican Terri Lynn Land, two things have always stood in the GOP's way. Michigan is just more naturally Democratic-leaning than the other big Senate battlegrounds of 2014, and Land hasn't been a strong enough candidate to deal with that effectively, despite good fundraising. Meanwhile, Peters's polling lead has grown steadily as more and more voters got to know him, making him a big favorite.

15. Virginia (D, Sen. Mark Warner) (Previous: 15)

Former Republican National Committee Chairman Ed Gillespie has made progress this year as he transitioned from political operative to political candidate, but Warner has held steady as a strong favorite all along. There is a small chance, though, that an "October surprise" could change all that: The Washington Post reported last weekend that Warner "discussed the possibility of several jobs, including a federal judgeship," for the daughter of a Virginia state senator "in an effort to dissuade him from quitting the evenly divided state Senate" earlier this year, according to what the former legislator's son told federal investigators. Is that enough to put Warner in jeopardy? Perhaps not. But it could nudge things a little closer than otherwise—and who knows if there might be other revelations about the episode.

16. Minnesota (D, Sen. Al Franken) (Previous: 14)

This race has been talked about for months as a potential sleeper, but three weeks from Election Day, it's still dozing. National money has completely skipped over the state, and per usual, Franken has been a fundraising machine, spending quickly as he goes, while businessman Mike McFadden has failed to make any breakthroughs. Franken has never trailed, or even come close to it, in a public poll—even one recently released by the state GOP. Franken's first race was the closest in the country, but there's going to be less drama this time around.

17. Oregon (D, Sen. Jeff Merkley) (Previous: 16)

As one columnist wrote for the Portland Oregonian, Republican Monica Wehby has hit the "trifecta" of campaign pitfalls: embarrassing personal revelations, a plagiarized website (twice), and refusals to debate or sit down with the media. The moderate pediatric neurosurgeon once had Republicans giddy about their chances of expanding the map into solidly blue Oregon, but the campaign hasn't been kind to her. Merkley's lead has never looked to be in jeopardy, and it'd take something pretty extraordinary for this race to come into contention late.

This article is from the archive of our partner National Journal.

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