In each state, "establishment" Republican candidates have emphasized their conservative credentials — thus narrowing the party's philosophical differences.
Democrats say it's happening elsewhere — and that the candidates trying to give Republicans control of the Senate will prove too far right for centrist voters in November.
Republicans need to gain six seats to control the Senate. Holding Kentucky and Georgia against well-funded Democrats is crucial to their hopes.
Georgia, Kentucky, Oregon have closely watched Republican contests for Senate. Pennsylvania and Arkansas have feisty gubernatorial primaries. Idaho has a competitive House race.
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