McConnell has been one of President Barack Obama's fiercest critics, but Bevin accused the longtime senator of not being conservative enough.
Bevin spent $3.3 million in his bid as a political newcomer backed by various tea party groups. McConnell drowned him out with more than $9 million in spending. Outside groups spent millions more defending his conservative credentials.
McConnell had already shifted into fall campaign mode. He's been attacking Obama's health care law and coal regulations and trying to link Grimes to the president, who is deeply unpopular in Kentucky.
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