Republican Sen. Dan Coats of Indiana announced today that he will not seek a second term next year, creating the first open seat of the cycle for Republicans and only the third to date. Coats' decision was not entirely unexpected as rumors had been circulating for several months that he was thinking about retiring. The Republican bench in the state is pretty deep. Most of the seven GOP members of the state's congressional delegation are likely to look at the race, though only one or two will actually get into the contest. Indianapolis Mayor Greg Ballard has also been mentioned as a potential candidate. Democrats won a Senate seat in Indiana in 2012, which means that they will take a hard look at this race, but none the circumstances that worked in their favor in that election are likely to be present next year. As such, the race will remain in the Likely Republican column until - and if - credible opposition emerges.

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