NASHVILLE, Tenn. (WKRN) – James Mackler announced he is dropping out of the Senate race.

Mackler made the announcement on his Twitter account Wednesday night, saying his decision to suspend the campaign is about uniting his party against Republican candidate Marsha Blackburn.

“My candidacy for U.S. Senate has never been about me but about service to the country I love,” he wrote on Twitter.

He continued, “While this is a difficult decision, I am not done serving…. I will never be able to express my full gratitude to you and all of my supports for your enthusiasm, encouragement, and your belief in me.”

With Mackler’s withdrawal, former Gov. Phil Bredesen is the only Democrat in the race.

On the Republican side, Congressman Marsha Blackburn, former representative Stephen Fincher and businessman Larry Crim have all announced their campaigns.