"It's a corrupt Washington game and Claire McCaskill plays it — getting rich off government," the ad charges.
It says that McCaskill's "family pocketed $40 million in federal subsidies," with the background proof citing a recent Associated Press report that McCaskill voted for some bills that may have provided federal funds to low-income housing developments that were affiliated with McCaskill's husband.
Akin is fundraising off the ad as well, issuing an email to supporters on Thursday urging them to donate to help Akin reach a goal of 20,000 donations, and to keep the ad on the air.
His new ad comes the day after McCaskill released three ads featuring survivors of sexual assault reminding voters of Akin's controversial comments about "legitimate rape." The comments, when they broke in August, caused most of the Republican establishment to wash their hands of Akin, with even Mitt Romney calling for the candidate to exit the race.
But he persisted, and after the final deadline for him to exit the race passed, Akin picked up a number of prominent endorsements, most notably former GOP presidential nominees Newt Gingrich and Rick Santorum.
He now faces an uphill battle in a race that was once seen as a likely win for the GOP, as the three most recent polls put her ahead of the Republican.
Watch Akin's ad: