Updated at 3:38 p.m. ET
(CBS News) Republicans are watching the clock as they wait for a defiant Todd Akin to drop out of the Missouri Senate race following controversial remarks he made about rape and abortion.
The six-term conservative congressman insists he's not quitting -- he said on former Arkansas Gov. Mike Huckabee's radio show Tuesday afternoon that he's staying in the race.
"I haven't done anything morally or ethically wrong," Akin told Huckabee, saying the backlash against him "does seem like a little bit of an overreaction."
"We are going to continue this race for the U.S. Senate," Akin continued. "We believe taking this stand is going to strengthen our country, going to strengthen, ultimately, the Republican Party."However, Akin is facing intense pressure from within his own party to drop out of the competitive race against Democratic Sen. Claire McCaskill. He could easily do so -- before 5 p.m. Central Time today.
If Akin exits today, the state Republican party will have 28 days to replace him on the ballot. If today's deadline passes, Akin could still withdraw from the race before Sept. 25, but if he did so during that window, the Missouri GOP would have to obtain a court order to replace his name on the ballot. After Sept. 25, the state will not change the names on the state ballot, no matter what.
A close Akin confidant tells CBS News that he will consider his standing over the coming weeks in advance of the Sept. 25 deadline.
"He may ultimately decide the best decision for him and America is to step aside, but he's not going to rush to the judgment of the D.C. establishment who didn't want him to be the nominee to begin with," the Akin confidant said. "I know he is a very humble and considerate and thoughtful man and always has been his entire career, so he is not going to go away today. There is still time on his side. It may not be long, but there is time."
If Akin decides the financial support and resources aren't where they need to be, he could then obtain a court order to remove his name from the ballot by Sept. 25.
The two candidates who lost to Akin in the primary -- St. Louis-area businessman John Brunner and former Missouri state Treasurer Sarah Steelman -- are already jockeying behind the scenes to replace him.
"My mother is interested, but she's going to be a team player," Sam Steelman, who ran his mother Sarah Steelman's primary campaign, told CBS News. "The first goal in this is to get Claire McCaskill out of office. Right now, there's a lot of people, I guess, who feel that Todd Akin can't get it done, but Todd Akin obviously feels like he can get it done."
Akin beat both Brunner and Steelman in the Aug. 7 Republican primary to face off against McCaskill, one of the most vulnerable Democratic senators up for re-election this year. Even though polls showed McCaskill trailing all of her potential GOP competitors, Akin had the smallest lead against her. McCaskill and Democratic groups in fact spent money in the GOP primary to get Akin on the ballot.
This week's controversy started after Akin suggested that women couldn't get pregnant from rape.
"It seems to me first of all, from what I understand from doctors, that's really rare," Akin said in a local interview on Sunday when asked whether he would support abortions for rape victims. "If it's a legitimate rape, the female body has ways to try to shut that whole thing down," Akin said of a rape victim's chances of becoming pregnant.
While Akin maintains he's staying in the race for now, his support from the Republican party and national conservatives has all but vanished.
Mitt Romney called his comments "inexcusable," and his running mate Rep. Paul Ryan reportedly called Akin and told him to think about the repercussions of his remarks. Ryan reportedly stopped short of urging Akin to leave the race.
Several Republicans, however, including Senate Republican Leader Mitch McConnell, have explicitly called for him to get out of the race.
"In his heart of hearts, I'm certain that he is sincerely sorry for what he said but in this instance, when the future of our country is at stake, sorry is not sufficient," McConnell said in a statement Tuesday. "To continue serving his country in the honorable way he has served throughout his career, it is time for Congressman Akin to step aside."
Others calling for him to get out include Sens. Ron Johnson of Wisconsin, Scott Brown of Massachusetts and Roy Blunt of Missouri. Blunt on Tuesday released a joint statement with four former Republican Missouri senators calling for Akin's exit.
"We do not believe it serves the national interest for Congressman Todd Akin to stay in this race," the Missouri politicians said. "The issues at stake are too big, and this election is simply too important. The right decision is to step aside."
The National Republican Senatorial Committee (NRSC), meanwhile, told Akin Monday it would no longer financially support his Senate bid if he chooses to stay in the race and is now campaigning against Akin as if he were a member of the opposite party, alerting the media to the negative attention Akin is getting.
"It should not be lost on anyone that some of the only voices not calling for Congressman Akin to do the right thing and step aside are Claire McCaskill and the leaders of the pro-abortion movement," NRSC spokesman Brian Walsh said in a statement Tuesday. "Senator McCaskill knows that the only way she wins re-election is if Todd Akin is her opponent in November. We continue to hope that Congressman Akin will do the right thing for the values he holds dear, but there should be no mistake - if he continues with this misguided campaign, it will be without the support and resources of the NRSC."
Sen. John Cornyn of Texas, chairman of the NRSC, said in a public statement earlier that Akin's comments were "wrong, offensive, and indefensible."
Meanwhile, the Karl Rove-backed super PAC American Crossroads confirmed to CBS News that it is pulling its ads from Missouri. "The act speaks for itself," Crossroads said to CBS regarding its decision to pull its ads.
National conservative media, including National Review, Charles Krauthammer and the Wall Street Journal, declared Akin a sinking ship. Fox News television host Sean Hannity told Akin that he should consider dropping out because "elections are bigger than one person." Radio host Mark Levin similarly called on Akin to step aside.
The antipathy toward Akin extended beyond conservative media -- on Monday night, after Akin stood up CNN host Piers Morgan, Morgan called him "a gutless little twerp."
And even though the Romney campaign flatly condemned Akin's remarks, Democrats are trying to tie the GOP ticket and the Republican party in general to the controversial statements. President Obama on Monday said that Akin's remarks underscore "why we shouldn't have a bunch of politicians, a majority of whom are men, making health care decisions on behalf of women."
The Democratic National Committee, meanwhile, put a petition online that said "The Republican Party--led by Mitt Romney and Paul Ryan--is dangerously wrong for women."
"Mitt Romney would 'get rid of' federal funding for Planned Parenthood, Paul Ryan co-sponsored a piece of legislation that would have narrowed the definition of rape, and now Rep. Todd Akin of Missouri claims there's a biological defense against pregnancy from 'legitimate rape,'" the petition reads.
For Democrats, the issue presents an opportunity to revive the charge that Republicans are waging a "" and shore up their advantage among women voters.
Scott Conroy contributed to this report.