South Carolina Gov. Nikki Haley and two groups supporting her have spent nearly twice as much as her Democratic challenger, state Sen. Vincent Sheheen, and his backers.
Meanwhile, independent gubernatorial candidate Tom Ervin has outspent Sheheen.
That's according to an analysis released Wednesday by the nonpartisan Center for Public Integrity, using research from political advertising tracker Kantar Media/CMAG.
The data shows Haley's campaign directly spent $1.1 million on TV ad slots through Sept. 8, while the Republican Governors Association spent about $681,000, and a pro-Haley political group called the Movement Fund spent $163,000.
That compares to $763,000 spent by Sheheen's campaign and $260,000 by the Democratic Governors Association. Ervin spent $1.5 million.
None of the three campaigns responded to requests for comment on the data.