The establishment struck back.
Two weeks after House Majority Leader Eric Cantor's primary loss to a little-known and underfunded tea party challenger rocked the Republican Party, incumbent and mainstream GOP candidates came out on top in several high-profile primary showdowns.
In Tuesday's marquee race, longtime Sen. Thad Cochran of Mississippi narrowly fended off a fierce primary challenge from state Sen. Chris McDaniel, who edged Cochran in the primary three weeks ago. Cochran's victory might have come from crossover Democratic voters - courted by the senator - who cast ballots in the runoff.
Cochran was joined by Rep. James Lankford, who easily won the primary in Oklahoma over two other major candidates who enjoyed tea party support in the race to succeed a retiring senator. Former Rep. Bob Beauprez, considered the mainstream pick in Colorado's GOP gubernatorial primary, topped three other candidates. And former South Carolina Attorney General Henry McMaster, the ultimate insider, won a landslide victory in the state's Republican lieutenant governor runoff.
In another high-profile showdown, Democratic Rep. Charlie Rangel of New York, who was first elected to Congress 44 years ago, claimed victory in what he says will be his last campaign. But Rangel's opponent, state Sen. Adriano Espaillat, who nearly ousted Rangel in the Democratic primary two years ago, wasn't conceding the tight race early Wednesday morning.
And in Maryland, outgoing Gov. Martin O'Malley, a potential 2016 Democratic presidential contender, wasn't on the ballot but might have been the biggest winner of the night.
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