But Republicans found themselves facing an uphill fight in the Senate race after Akin made controversial comments about rape and pregnancy in late August that brought him widespread condemnation from GOP leaders.
Republican leaders eventually disavowed their candidate in Missouri, but Akin persisted, managing to rebound from an initial 10-point deficit in one poll conducted shortly after his comments to pull within 4 points in a poll taken a week before Election Day.
Those numbers prompted a flood of outside money supporting him, but McCaskill went on to win the seat by more than 15 points.
McCaskill added, however, that Romney's strength in Missouri helped to buoy Akin throughout the race. She was one of five Democratic Senate candidates elected in states where voters also chose Romney. The other states are North Dakota, Indiana, Montana and West Virginia.
"That meant that voters made individual choices, and so that was making sure they understood that I was a more desirable alternative than Todd Akin, and that was something that took a little while to get done," she said.