By ERIK SCHELZIG, Associated Press

NASHVILLE (AP) - Conservative activist Andy Ogles is running for the U.S. Senate seat held by Tennessee Republican Bob Corker, who has so far refused to divulge whether he will seek a third term.

Ogles heads the Tennessee chapter of Americans for Prosperity, a group funded by billionaire brothers Charles and David Koch.

The Koch network has aggressively pushed to repeal former President Barack Obama's health care law in Congress, and Ogles helped lead successful efforts to torpedo Republican Gov. Bill Haslam's efforts to expand Medicaid in Tennessee.

The national group has often displayed a willingness to take on Republicans - including President Donald Trump - when their policies aren't deemed conservative enough, and the network announced plans in June to spend up to $400 million in the 2018 midterm elections.

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