Why a Defiant Todd Akin Could Cost Republicans Control of Senate

For the second time in as many days, Todd Akin took to Mike Huckabee's radio show to confirm he will not be withdrawing his name from Missouri's U.S. Senate race. This time, however, his announcement was in light of five former Republican senators from Missouri and nine other current GOP senators who have all called for Akin to drop out.

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The importance of this Senate seat to the GOP's chances of taking control of the Senate cannot be underestimated. It is not impossible for Republicans to pick up the four seats (three, if Romney wins the White House) needed for a majority without Missouri. But it will be a long, hard slog.

Before the Akin eruption Monday, incumbent Sen. Claire McCaskill, D-Mo., was considered the most vulnerable Democratic senator in the country. Recent polling showed her trailing Akin by 5 points, 45 to 49 percent.

If McCaskill wins, Republicans would need to win four of the five most vulnerable Democratic-held seats - Nebraska, North Dakota, Wisconsin, Virginia and Montana - while not losing any of their own vulnerable seats, such as Massachusetts, Maine, Nevada or Indiana. At this point, Republicans are favored to win Nebraska while Democrats have the edge in Maine.

With Akin sticking to his bid, if Republicans stick by their commitment not to help or fund him, they are essentially writing off a path to the majority. That is pretty astounding.

It is also a powerful reminder of just how dangerous Republicans believe the gender gap is for them. They would rather lose a Senate seat, and potentially the majority, than lose the race for the White House because they were completely abandoned by women voters.

Akin has until 6 p.m. ET today to withdraw.