I would put my money on Akin simply based on the hatred of McCaskill that exists and is being amplified by her proven corruption. After Akin’s gaffe, Republicans expected him to lose at least half of his support. Stick a fork in him... but he’s lost very little. This tells me that Missouri voters who want McCaskill out are 100% committed to getting her out, and are therefor more likely to come out to vote on election day.
Akin's gaffe is history. Michelle Bachmann's had gaffes.
We should stop reminding the republicans who made those predictions and try to move forward.