NASHVILLE, Tenn. (AP) - Months of bruising primary campaign activity comes to a close Thursday as voters head to the polls to decide the winners.

Among the most closely watched contests are efforts by U.S. Reps. Chuck Fleischmann and Diane Black to win re-election to their second terms in Congress.

Both have faced strong challenges for the Republican nomination, and both races have featured large amounts of outside money in the form of independent expenditures.

The Democratic nominee for the U.S. Senate is also set to be determined Thursday. Incumbent Sen. Bob Corker has a large fundraising and name recognition advantage over his GOP opponents.

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