If Rep. Todd Akin (R) does drop his Missouri Senate bid within the next 24 hours, as the GOP establishment is pressuring him to do, at least his timing will be impeccable.

Missouri state law allows a nominated candidate to withdraw his or her bid for office by 5 p.m. on the 11th Tuesday before the election which, as it turns out, is tomorrow. If Akin does drop his bid before tomorrow’s deadline, the state’s GOP central committee would pick his replacement.

This statutory fact alone is why Republicans — from National Republican Senatorial Committee Chairman John Cornyn (Texas) to presumptive GOP presidential nominee Mitt Romney to Senate Minority Leader Mitch McConnell (Ky.) — are coalescing around a 24-hour ultimatum.

“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,” Cornyn said in a statement, minutes after Akin wrapped a radio interview with Mike Huckabee.

In that interview, Akin expressed contrition about his controversial remarks regarding “legitimate rape” and confidence he could stay in the race and win. Akin later tweeted a plea for donations: “I am in this race to win. We need a conservative Senate. Help me beat Claire [McCaskill] by donating.”

But support for Akin remaining in the race has collapsed in the past 12 hours, with sources saying the NRSC is planning to pull the $5 million in TV ad reservations it has in the state if Akin stays in the race.

If for some reason Akin does not drop his bid by tomorrow’s deadline, he could withdraw via a court order as late as Sept. 25. In that case, state law would require Akin to cover any costs for reprinting ballots and again, the central committee would select a substitute candidate.

The central committee has 28 days from a candidate’s withdrawal to name a replacement, so if Akin were to drop out tomorrow, Missouri Republicans would need to name a new candidate by Sept. 18. From a competitiveness and fundraising perspective, however, the GOP would likely try to name a replacement sooner.

A request for comment from the Missouri Republican Party was not immediately returned.