This article is from the archive of our partner National Journal

It's been 190 days since Texas kicked off the 2014 midterm primary elections in March, and the curtain finally closed on the last nominating contests of the year Tuesday in the Northeast. The general election looms, but a review of the last half-year highlights a number of important political lessons that will remain relevant well beyond 2014. Here are seven important takeaways from the 2014 primaries:

Incumbents still rule the roost "... but not as easily as they used to.

Just four congressional incumbents lost primaries in 2014, none of them senators, a departure from several tumultuous years of primary challenges. But more of those wins took harder work than usual. Fewer and fewer incumbents are running unopposed each election, and the rate of incumbents finishing under 60 or 70 percent in their primaries has more than doubled in recent elections. Four senators (Democrat Brian Schatz and Republicans Pat Roberts, Lamar Alexander, and Thad Cochran) finished with less than half of their primary vote.

Those members and others will be perfectly happy with their wins despite the margins. But it's not hard to draw a line between the growing number of incumbents with primary worries—worries stoked by the occasional shock loss of someone like former House Majority Leader Eric Cantor—and the declining number of incumbents from safe seats willing to cross party lines on key congressional votes.

Challengers have access to more money than ever.

Altogether, Senate candidates challenging incumbents in primaries raised nearly $19 million in 2013 and 2014, according to a review of the most recent campaign finance data from the Federal Election Commission. That's a lot of money; for reference, primary challengers to incumbent senators raised around $22 million over the previous three election cycles (2008, 2010, and 2012) combined.

Even fairly recently, incumbents used to be able to pretty much shut off fundraising for any challengers they got. But now, there are more ways to access money—like the grassroots conservative donor networks that come with endorsements from groups like the Club for Growth or Senate Conservatives Fund.

That's part of the reason why so many more incumbents in both the House and Senate got lower levels of primary support this year: More of their opponents had a basic amount of resources necessary to run a campaign, and some had even more than that basic level. As Josh Holmes, an adviser to Senate Minority Leader Mitch McConnell, has pointed out, many of these 2014 candidates got fewer votes than previous insurgents who managed to raise seven figures. But that doesn't change the fact that more candidates now have access to enough resources to give sitting members of Congress tougher races for renomination.

Primaries can help, Democrats.

One of the most remarkable disparities between Republicans and Democrats this year, especially in the Senate, was the differing number of primaries. Republicans had a competitive intra-party race just about everywhere, whether there was a sitting incumbent or an open-seat contest. Democrats did not. In every single general election battleground, the party's nominee was granted a free pass through the primary. (The fierce battle in Hawaii, a safe seat, doesn't count.)

Their absence was a luxury to most Democratic candidates, who could immediately focus on the general election. But the vetting process that occurs during primaries also helps parties avoid baggage-heavy nominees. And in that case, one might have helped Democrats avoid lining up behind John Walsh before anyone knew the former lieutenant governor had plagiarized most of his thesis while attending the Army War College. The revelation forced Walsh to quit the race, left Democrats without a credible candidate, and all but handed back to the GOP a seat the party had held for a hundred years.

Competitive primaries can also boost the political chops of its participants, something that could have helped the candidacy of someone like Bruce Braley in Iowa. The safe-seat congressman hadn't competed statewide before his current effort, and his early missteps opened the door to a stiff Republican challenge. Better sometimes to knock off the rust in a primary.

The NRSC still has game.

The last two election cycles, critics have either derided the National Republican Senatorial Committee as too heavy-handed within primaries or mocked its feckless attempts to stop tea-party challengers. The criticism—whose impact was evident when GOP leaders were forced to search long and hard for a new chairman—was loud enough that it was fair to wonder if the political committee's importance had diminished.

But those concerns were pushed aside earlier this year, when the NRSC persuaded Cory Gardner to launch a late-breaking campaign against Mark Udall. Getting the telegenic congressman to reverse himself—he had decided last year he wouldn't run for Senate—was impressive enough. Just as important was persuading a trio of existing GOP candidates, including 2010 nominee Ken Buck, to step aside and save Gardner a primary. (It's no coincidence that days after Gardner became the de-facto nominee, he began repositioning himself on sensitive topics to court a general-election audience.) It's not the kind of deft internal maneuvering that was evident in 2010 or 2012, and it single-handily put Colorado's Senate race on the midterm map.

Along with the committee's successful incumbent-protection efforts in Kansas and Mississippi, the Gardner coup was proof of the NRSC's continued relevance. If Republicans retake the Senate, this election might count as a full-blown rebound.

Message to conservatives: Tactics matter.

Conservative insurgents weren't held back by the environment—they were held back by their own underwhelming performance on the campaign trail. Too many of the groups that make up the "tea-party establishment" wasted tens of thousands of dollars on politically useless accoutrement like yard signs (or worse). Candidates who did receive the full-throated support of Club for Growth and others were nonetheless drowned in negative ads from establishment-friendly organizations. In the Mississippi Senate primary, the insurgency's best chance to knock off an incumbent, conservatives were outwitted by an ingenious plan from Thad Cochran's team to court black voters.

The conservative movement could get away with sloppy execution in 2010 and 2012, when Republican incumbents and their allies were still fumbling their response to the tea-party movement. But groups like the U.S. Chamber of Commerce and American Crossroads devised sophisticated, successful battle plans this year and clearly outperformed their counterparts.

Most conservative strategists don't dispute they need to improve, and many are already rethinking their approach to primaries. One intriguing idea: Ditch the "tea party" label. It's the kind of new idea they'll need if they want to avoid a repeat of this year's disappointment in 2016.

A good ad still matters.

Not many people took notice of Joni Ernst when she started her campaign for Senate in Iowa. Nobody considered David Perdue a juggernaut, either, when he started running in Georgia—especially with three congressman and a former statewide officeholder already eyeing the GOP nomination.

But both candidates had something their rivals didn't: A memorable TV ad. Ernst's spot barely ran on TV in Iowa, but the image of her castrating hogs was enough to capture national attention. And the Perdue campaign's depiction of its opponents as crying babies—a theme it revisited frequently during the primary—turned him from just another candidate to the race's front-runner.

There's a lot of focus in Republican primaries over the battle between tea-party and establishment-backed candidates, and rightfully so. But sometimes a memorable ad—a difficult accomplishment in an increasingly cluttered media environment—is all a winning candidate really needs.

"Meddling" in the other party's primary is really difficult.

Messing around in the opposing primary to try and boost a less-electable candidate is a sexy strategy these days—especially after Senate Democrats used it to help win races in two successive elections by promoting self-destructive Republican candidates (Nevada's Sharron Angle and Missouri's Todd Akin). But the party came up empty this year, trying it in a number of House, Senate, and gubernatorial races where the strongest GOP nominee still won, often by a wide margin.

In the end, the attention those two successes got was out of line with the overall effectiveness of the strategy. "Because of the success with Akin, I feel like it's this new trendy thing," one Democratic strategist said. "I've been on calls where people are like, maybe we should screw with their primary. But you shouldn't do it nine times out of 10, or maybe 95 out of 100. It's very easy to get a backlash, and we don't know how to poll hardcore Republicans—as a Democratic pollster, you're just guessing."

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

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