WICHITA—Pat Roberts needed help, and the cavalry arrived. On Monday, Mitt Romney, Bob Dole, and Sen. Ron Johnson of Wisconsin stumped for him. On Tuesday, it was Rand Paul.

"I'm very proud to have virtually every segment of the Republican Party come out and say they're endorsing me because they know me, they trust me," Roberts told National Journal. "That's a very humbling thing."

This star-studded lineup of surrogates from across the GOP spectrum says just how important this contest is to national Republicans. As Roberts says, and he says it a lot, his race could very well decide Senate control for the next two years.

But the contrast between moderate Republicans and base-rallying conservatives coming to Kansas on Roberts' behalf says something else as well: The GOP incumbent is fighting a two-front war to keep his seat. He needs the conservative Republicans who opposed him in the primary to come home, and he also must hold on to the moderate members of his party who might be giving independent candidate Greg Orman a serious look.

It's a tall order for any candidate, and one Roberts' allies say has been a challenge.

The battle has been waged on multiple levels. Publicly, Roberts brings in surrogates from all corners of the Republican Party, all the while relentlessly telling voters that his race is not about him but about Senate control. Behind the scenes, he's reached out to GOP base voters with messages reassuring them he's sufficiently conservative. And of course, Roberts and his allies have been pummeling Orman on TV, putting millions into ads tying him to President Obama and Senate Majority Leader Harry Reid.

Roberts, who survived an August primary challenge from the tea party-aligned Milton Wolf, had been expected to coast through the general election. But Democrat Chad Taylor's decision to drop out of the race in August put Roberts in a one-on-one matchup with Orman, and Roberts has had to fight for his political life here in Kansas.

Recent polling shows a margin-of-error race: Orman leads by less than a percentage point in the RealClearPolitics polling average. Roberts has been hit both over residency issues and for missing important committee hearings in the Senate. And all this is happening as GOP Gov. Sam Brownback, also on the ballot this fall, is facing serious problems with moderate Republicans in his campaign for second term.

These circumstances have amounted to what one GOP operative described as "the perfect storm."

Roberts is "having to fight a multifront war," said veteran Kansas politics observer Chapman Rackaway, a political science professor at Fort Hays State University. "Roberts doesn't really have a strong base of support in either wing of the party [moderates or conservatives]; he has soft support in both wings."

Roberts, for his part, makes the same pitch no matter who he's talking to: A vote for him is a vote for a Republican-controlled Senate, and a vote for his opponent is one for Obama and Reid. It's his main talking point at every campaign event as he reads from notes on stage, and he brings it up in the answer to every question he gets (from voters and reporters alike).

"Ladies and gentlemen, the road to a Republican majority now runs straight through Kansas, and Kansas will deliver," Roberts told the crowd in Overland Park on Monday.

"The race is about so much more than electing me, Pat Roberts," he said Tuesday in Wichita. "The eyes of the country ... are on Kansas because it's up to us to elect a Republican Senate."

Roberts and his team are betting that in deep-red Kansas, where registered Republicans outnumber registered Democrats almost 2-to-1, even GOP voters who aren't thrilled about him will respond to the relentless focus on Senate control. The most recent polling in the state, from NBC/Marist, put President Obama's approval rating at 33 percent.

Romney and Paul, too, mainly focused their arguments on national issues when stumping for Roberts.

"A vote for Greg Orman is a vote for Barack Obama, and America should not make that mistake three times," Romney told the crowd.

"If you elect 49 Republican senators and leave Pat Roberts, we will get zero percent of the agenda," Paul said in Wichita. "You'll get 100 percent Harry Reid, you'll get 100 percent liberal agenda."

But their pitches contained subtle differences, language meant to appeal to different segments of the Republican Party, all of which need to turn out for Roberts if he is to keep his seat.

Romney, for instance, spoke about Roberts and his Republican Party colleagues as the ones with solutions for business and job creation. "Lest we not communicate this clearly to the people of the country and of Kansas, it is essential to understand when we're talking about businesses, small businesses—that's not because we just love businesspeople, it's because we love the jobs they create," he said.

Paul, speaking at an airplane hangar in Wichita, recalled his own "divisive" Republican primary in 2010, using the example as an indirect plea to Republicans here to "come together" behind Roberts after the August primary. "I understand on occasion Republicans fight. Is that true?" he asked the crowd, which responded with laughter. "When our primary's over, we come together, because we're a lot better than the Democrats."

Paul's new TV ad, a six-figure buy that started in Kansas this week, stresses Roberts's vote against "sending billions [in foreign aid] to countries that hate us"—an issue that appeals to both GOP base voters and more libertarian-leaning Republicans.

It's not only headliners who have shown up to save Roberts' seat. When the race heated up in September, the National Republican Senatorial Committee sent two GOP operatives, Chris LaCivita and Corry Bliss, to replace Roberts' existing staff and give the campaign a new direction. The national party has gotten other staffers involved, aided the Kansas GOP's ground-game efforts, and spent six figures on the airwaves—all that in addition to lining up the surrogates.

There's reason for Republicans to have some cautious optimism, at least when it comes to winning over conservative Kansans. While Roberts still hasn't gotten an endorsement from his primary challenger—who was reportedly considering endorsing Orman over his former GOP foe—the Tea Party Patriots announced Tuesday that they would back Roberts.

"There is just too much at stake not to back Pat Roberts," Tea Party Patriots Chairwoman Jenny Beth Martin said in a statement, adding that the group's members in Kansas "overwhelmingly supported" the decision to endorse.

Roberts is banking on that sentiment. Indeed, he insists that the Republicans who backed Wolf did so less because they dislike their incumbent senator and more because they were particularly inspired by Wolf himself. "I've got a pretty strong conservative record and very strong conservative credentials, so I don't think it was anything anti-Roberts so much as it was for my opponent," Roberts said. "That's done—we've made significant outreach to those folks so I think they'll be on board."

But winning moderates' support is still uncertain. Visits from national, mainstream figures like Romney and Jeb Bush have helped; former GOP Gov. Bill Graves, who still has a lot of sway here, recorded a radio ad for Roberts to boost his numbers among moderates.

"Most people would think of [Graves] as the moderate Republican governor. He just came out and endorsed Roberts, in a real nice radio ad," said Kansas GOP executive director Clay Barker. "That reassures people that Roberts is not too far to the right."

But Roberts' problem with moderates is compounded by Brownback's troubles among that wing of the GOP. Brownback's conservative reforms in the state have earned him the ire of moderate Republicans, many of whom have ditched his campaign for Democrat Paul Davis. While their issues are with Brownback, not Roberts, they might not distinguish when they reach the voting booth.

Still, Roberts aides argue that momentum has been on their side the last few weeks. The race is still far too close for their comfort: The most recent NBC/Marist poll, released Sunday, found Roberts trailing Orman by 1 point. That's an improvement from the 10-point deficit Roberts had in the early October NBC/Marist poll, but it still means both campaigns could have a long election night.

Though Roberts's favorability rating continues to be underwater—NBC/Marist had him at 43 percent favorable, 46 percent unfavorable—Republicans have succeeded in turning more voters against Orman. Earlier in October, Orman's favorability rating was 46 percent favorable, 26 percent favorable; that's now shifted to 42 percent favorable, 37 percent unfavorable.

Orman's rising unfavorables are part of the reason GOP observers here say the national focus is helpful—and the reason Roberts is running several points ahead of Brownback.

"Roberts has an advantage that Brownback doesn't have, in that he can say, 'Well, if you don't like me, fine, but remember [it's a] vote for Mitch McConnell,'" said Wint Winter, a former GOP state senator who's heading the moderate Republican opposition to Brownback. "There's no bonus, if you will, to voting for Brownback like there is voting for Roberts because of this argument that control of the U.S. Senate's at risk."

Orman dismisses Roberts' strategy of nationalizing this contest.

"I don't think the senator can hide behind his party label," Orman told National Journal during a campaign stop in Olathe. "I think the senator needs to go out there and make a positive statement for what he's going to do, and he just hasn't done that."

So while Republicans are pushing resources to Kansas and seeing some poll movement in their direction, Orman's allies are upping their last-minute spending to keep the race tilted in their favor. The Committee to Elect an Independent Senate and Mayday PAC both have spent significant money on ads backing Orman, supplementing Orman's own investments.

Per The Washington Post, Roberts' allies have spent $3.8 million in ads for the final two weeks of the campaign, compared with $3.1 million for Orman. Even when it comes to money, this one remains too close to call.

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