NASHVILLE (AP) — Democratic Nashville attorney and former Army helicopter pilot James Mackler is the first candidate to announce a 2020 bid for the seat Republican U.S. Sen. Lamar Alexander will leave after his term.

Mackler told the AP Tuesday about his Senate bid plans. In an announcement video, the 46-year-old says he's not a politician and President Donald Trump is making life harder across Tennessee, citing health care, the tax law and the trade war.

Mackler started a 2018 Senate bid before former Republican Sen. Bob Corker decided not to seek re-election. Mackler later stopped running and endorsed Democratic ex-Gov. Phil Bredesen, who lost to new Republican Sen. Marsha Blackburn.

Republican Gov. Bill Haslam, who leaves office this month, is mulling a run to replace Alexander.

Republicans have held both Tennessee Senate seats since 1994.