Working swiftly to preserve its chances of claiming a new Senate seat, the Republican Party is urging Rep. Todd Akin of Missouri to surrender his Senate candidacy before a Tuesday deadline to drop out.

The embattled Akin, who recently prevailed in a three-way Senate primary, caused an uproar by suggesting on Sunday that women's bodies could prevent pregnancies in cases of "legitimate rape." He has since faced intensifying calls to exit the race, where Republicans believe they have -- or had, before Akin's blunder -- an excellent chance of unseating incumbent senator Claire McCaskill, a Democrat.

Missouri law stipulates that candidates can withdraw up until 11 weeks before election day, which in this case is 5:00 on Tuesday. If Akin does not drop out before this evening a court order would be needed to strike him from the ballot.

With that deadline fast approaching, Republicans suggested with varying degrees of intensity that Akin cede his nomination. Presumptive Republican nominee Mitt Romney distanced himself from Akin, saying that he disagreed with the Missouri Republican, and Senator Scott Brown of Massachusetts said there is "no place in our public discourse for this type of offensive thinking" in calling Akin to step aside. 

The national party apparatus also kicked into action. The National Republican Senatorial Committee said it was withdrawing financing, including millions already earmarked for advertisements. Senator John Cornyn of Texas, who oversees Republican Senate campaigns, issued a statement strongly suggesting that Akin exit.

"Congressman Akin's statements were wrong, offensive, and indefensible," Cornyn said. "I recognize that this is a difficult time for him, but over the next 24 hours, Congressman Akin should carefully consider what is best for him, his family, the Republican Party, and the values that he cares about and has fought for throughout his career in public service."

Crossroads GPS, a conservative advocacy group that had poured millions into Missouri, said it was suspending its operations there. And conservative opinionmakers exhorted Akin to act in the interest fo the party, with Sean Hannity saying that "sometimes an election is bigger than one person."

Akin has steadfastly insisted throughout that he will stay the course, and released an advertisement in which he looks directly into the camera and asks for forgiveness.

"Rape is an evil act," Akin says in the advertisement. "I used the wrong words in the wrong way and for that I apologize."

Should he choose to remain in the race, Akin will have at least one person who backs his decision to remain: his opponent, Sen. McCaskill. After pummeling Akin for his insensitivity, McCaskill said that forcing him to withdraw would undercut the will of Missouri voters.

"I really think that for the national party to try to come in here and dictate to the Republican primary voters that they're going to invalidate their decision, that would be pretty radical. I think there could be a backlash for the Republicans if they did that," McCaskill said during an appearance on the program "Morning Joe."

Preliminary polling shows that Akin's comments have not yet damaged his prospects. A Public Policy Polling analysis found that voters strongly disagree with Akin's comments but still support him over McCaskill by a razor-thin margin of 44 to 43.