Republican Senate leader Mitch McConnell easily beat a Tea Party primary challenger in Kentucky on Tuesday, setting up one of November's most expensive and hard-fought Senate races against Democrat Alison Lundergan Grimes.
Establishment-backed Republicans also swept away Tea Party rivals in Georgia and Oregon, extending the establishment's winning streak against the Tea Party and bolstering Republican chances of retaking the Senate in November.
McConnell's decisive victory over conservative businessman Matt Bevin headlined the busiest election night of the year so far, as voters in six states picked candidates for November elections that will decide which party controls Congress.
Republicans need to gain six seats to recapture Senate control and party leaders have waged a successful effort to avoid divisive primaries that produced weak candidates and helped cost them Senate races in 2010 and 2012.
Senate candidates backed by the party establishment won races earlier this year against the Tea Party in Texas and North Carolina.
McConnell had been targeted by Tea Party and conservative groups that accused him of not doing enough to block President Barack Obama's agenda in the Senate, but Bevin's political inexperience showed in a series of campaign-trail missteps, including his attendance at a rally supporting cockfighting.