Manchin is a Democrat and Daniels is a Republican.
The debate in Indiana between Daniels and former Democratic Rep. Jill Long Thompson was over privatizing state assets and agencies.
Manchin, a popular governor and considered the likely successor to U.S. Sen. Robert Byrd when he eventually vacates his Senate seat, was challenged by Republican Russ Weeks, a state senator.
Eleven states are conducting gubernatorial races.
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