Former Sen. Dan Coats (R-Ind.) is expected to announce Wednesday that he will challenge Sen. Evan Bayh (D-Ind.) in November, the Howey Political Report reported Tuesday evening.

Bayh first won his Senate seat in 1998, when Coats retired. He has had little trouble winning re-election despite the Republican lean of his state. He has also warded off competitive challenges by stockpiling a huge campaign war chest. As of Dec. 31, Bayh had close to $13 million in his re-election fund.

Coats would quickly become the frontrunner for the GOP nomination to face Bayh in November. Among the Republicans in the race are state Sen. Marlin Stutzman and former Rep. John Hostettler.