SANTA FE, N.M. (AP) — A Democratic contender for New Mexico's northern congressional seat in 2020 elections says he is leaving the race and endorsing another likely candidate.

Air ambulance business manager Mark McDonald of Raton on Wednesday said he's dropping out of the race to succeed U.S. Rep. Ben Ray Luján. McDonald is voicing support for a possible candidacy by Santa Fe-based District Attorney Marco Serna, who has launched an exploratory committee.

The 27-year-old McDonald ran unsuccessfully in 2018 as a Democrat and openly gay candidate for a state House seat held by Republican Jack Chatfield. McDonald says he likes Serna's approach to economic and public health issues.

Candidates actively pursuing the 3rd Congressional District seat include state Rep. Joseph Sanchez of Alcalde and Santa Fe-based attorney Teresa Leger. Both are Democrats.