Senator Thad Cochran of Mississippi edged out challenger Chris McDaniel in the Republican primary runoff Tuesday, ending a hard-fought, often bitter campaign for the party’s nomination for the Senate. Cochran won the runoff by just around 4000 votes, and is a favorite to win the general election.

McDaniel actually won the June 3 primary, which had much lower turnout than Tuesday’s runoff, but he failed to win more than 50 percent of the vote. Tea Party groups had strongly backed McDaniel’s challenge from the right, while groups like the Chamber of Commerce and the Mississippi Republican establishment threw their weight behind the six-term senator. Cochran also reportedly campaigned directly for the state’s black Democratic vote, which may have helped him over the line in the runoff.