Three weeks after Republican Rep. Todd Akin upended the national political landscape by claiming that pregnancies rarely result from “legitimate rape,” the race for Senate in this increasingly conservative state — and in many ways the battle for control of Congress’s upper chamber — has settled into a waiting game.

A Sept. 25 deadline looms. That’s the last day Akin can petition Missouri courts to remove his name from the ballot — and comply with the near-universal calls from party leaders who think his comments have made unwinnable a seat they need for an easier path to a Senate majority.

Akin’s opponent, Democratic Sen. Claire McCaskill, is waiting, too — hoping that Akin remains in the race but knowing that even if he does, reelection to the Senate is far from secure in a state that has turned sharply against President Obama.

In the balance could lie the Senate.

Republicans need four new seats to take control of the chamber. That appeared to be within closer reach for the GOP earlier this year, before Akin’s comment — for which he has apologized — and before Sen. Olympia Snowe (R-Maine) announced her retirement, putting her seat in play.

To win control now, Republicans must see a series of neck-and-neck races turn their way — a surprisingly thin margin of error in a year when nearly two dozen Democratic senators are up for reelection.

“The easiest path to a Republican majority went through Missouri. Without it, it’s steeper and a little more circuitous,” said Jennifer Duffy, an analyst for the nonpartisan Cook Political Report. “It can be done — but they need all the breaks.”

Stuart Rothenberg of the Rothenberg Political Report agreed. The Senate is “still up for grabs,” he said. But he added: “It’s looking harder for Republicans.”

Akin’s rape comments on Aug. 19 breathed new life into McCaskill’s struggling campaign. Now her challenge is to convince Missouri voters that her opponent is too radical not only on women’s issues but also across a range of topics.

And so last week, while speaker after speaker at the Democratic National Convention — which McCaskill subtly skipped — alluded to Akin’s stand on abortion, McCaskill embarked on a tour of Missouri college campuses.

“Congressman Akin is extreme and out of the mainstream,” McCaskill told students at Northwest Missouri State University. Akin, she said, “doesn’t understand what his policy positions will do to this state and to the country that we all love.”

But she was not talking about his “legitimate rape” remark, which would have required her to dwell on the touchy issue of abortion. Instead, she was referring to Akin’s contention, in an April debate during the Republican Senate primary, that federally backed student loans represent a “Stage 3 cancer of socialism.”

McCaskill called his position a “head scratcher” in her appearances last week, part of her effort to extend Akin’s controversial remarks to the other corners of their hotly contested Senate race.

“This race will be hard-fought and close,” McCaskill said in an interview. “Anybody who doesn’t think it’s going to be hard-fought and close hasn’t spent much time on the ground in Missouri.”

A St. Louis Post-Dispatch/Mason-Dixon poll taken in the days after the controversy showed McCaskill ahead by nine points, but other polling has indicated a much tighter race.

GOP Senate setbacks

The Akin fiasco is only the latest setback for Republican ambitions to take the Senate.

After Snowe announced she would not seek reelection in Maine, former governor Angus King, a popular independent, announced he would run to replace her, probably taking the state out of the Republican column and forcing the GOP to win five seats to guarantee control.

Then came Akin’s interview, on a local St. Louis television station, in which he defended his position of opposing abortion even in cases of rape and incest.

Republicans say they still feel confident about picking up a seat in Nebraska, where polls show Democratic former senator Bob Kerrey trailing Republican Deb Fischer to replace Sen. Ben Nelson (D), who is retiring.

But to win the chamber, Republicans will also have to win a collection of races in which polls have been exceptionally tight. Their opportunities lie in North Dakota, where Democratic former attorney general Heidi Heitkamp has been running closer than expected with Republican Rep. Rick Berg, as well as in Virginia, Montana, Ohio and Florida.

Even with closer-than-expected contests in Wisconsin and Connecticut, the GOP will need a series of good breaks between now and November — and perhaps a strong pull from the top of the ticket by Mitt Romney — to take the Senate.

Republicans had not figured that one of those breaks would have to come in Missouri.

Immediately after Akin’s remarks, the National Republican Senatorial Committee (NRSC) vowed to spend no money on his race, echoing the disdain of a leading independent super PAC associated with Karl Rove. Rove grew so frustrated with Akin’s refusal to drop out that he jokingly insinuated to wealthy donors at the Republican National Convention about having Akin “murdered.” He, too, apologized.

Without national support, Akin seemed vulnerable to a coming onslaught of McCaskill advertising expected to hit him on his abortion comment, as well as on student loans and his opposition to the minimum wage and school lunch programs.

On Friday, several Missouri television stations said they were canceling Akin ad buys after receiving only half of the scheduled payments, a sign the campaign may already be running out of cash. Campaign officials said they were merely reallocating dollars to spend more closer to Election Day.

National Republicans say there is no chance they will return to the race, noting that GOP officeholders in Missouri have declined to campaign with Akin and that the NRSC has even canceled $3 million in reserved ad time in the state.

But Akin advisers are not flinching. They say McCaskill remains beatable — her popularity has taken a dive here and she is vulnerable because of votes in favor of key Obama agenda items, including the stimulus and the health-care overhaul.

They say D.C. Republicans ultimately will not stay out of a race so critical to their national prospects — if they are convinced Akin won’t end his campaign.

“Todd is in the race. That’s a fact,” said Rick Tyler, an Akin adviser. “They can either help or they can continue to abandon the race. And if they lose the Senate majority, they’ll have only themselves to blame.”

Akin backers

Akin has lately gotten encouraging signs from local Republicans that appear to be buoying his resolve to stick it out — and hurting the party’s chances of taking the seat.

Two weeks ago, the Republican committee for the 8th Congressional District — representing more than two dozen Missouri counties — passed a resolution of support for Akin, the latest of several local Republican groups here to do so.

The campaign indicated Akin will announce next week that he has accepted invitations to debate after Sept. 25 — a renewed public statement of his intention to remain in the race.

But the division in Missouri is deep. Even the Missouri delegation at the Republican convention in Tampa expressed uncertainty. Some Missouri delegates wore “Akin for Senate” stickers as a sign of support, while others spoke openly about the shame he had brought the delegation.

“It was bad at home, it was bad on the road, it was bad at the airport, and it’s bad here,” said Kay Hoflander, a Missouri delegate at large.

Speaking off to the side from the delegation’s seats beside the convention stage, she said that before coming to Tampa, her local chairman’s office had been inundated with calls from former Akin supporters saying, “Come get this 4-by-8 sign off my lawn!”

When a storm canceled convention activities, the Missouri delegation hunkered down for a “Hurricane Dinner” of chicken and pizza at the airport Marriott and argued over their candidate.

At one table, Ralph Munyan, a Kansas City lawyer and delegate, listened as a fellow delegate told him she would not vote for Akin if he were the nominee. Another said many of her friends had “totally written off” Akin and intended to vote for McCaskill.

But Munyan, who was originally not a supporter of Akin and was also upset by the rape remark, nevertheless had taken to wearing an Akin sticker to protest party strong-arming and the way “the state party dropped Akin like a hot potato.”

That backlash — stoked by strong support from former Arkansas governor Mike Huckabee, who has railed against party bosses — has tempered McCaskill’s expectations and heartened Akin’s campaign.

They say Rove’s remarks and the meddling of national Republicans have boosted fundraising.

And last week, a videographer appeared at a McCaskill event at the University of Missouri at Kansas City — trying, on behalf of a national pro-business group, to get the Democratic incumbent on video talking union issues. That could be a sign that national groups might find ways to get more quietly involved, despite the talk of skipping the race.

Fred Wszolek, a strategist who serves as the spokesman for the Alexandria-based Workforce Fairness Institute, confirmed that his group — represented in the state by the Coalition to Protect Missouri Jobs — sent the cameraman.

He said the group is not a campaign organization but that it merely wants to get McCaskill on record stating her opinion of “microunions,” department-by-department organized units recently allowed by a ruling of the National Labor Relations Board.

“We’re not playing in the campaign,” he said. “We’re engaged in issue conversation.”

The group is active in Virginia and Montana, two other key Senate swing states. Asked if the organization is likely to run ads in Missouri explaining to voters McCaskill’s view on the issue, Wszolek said, “I couldn’t say.”