Aug. 23 (UPI) -- The Democratic presidential field grew smaller again Friday, with Rep. Seth Moulton dropping out of the race -- saying only three candidates are in serious contention for the party nomination.
Moulton told The New York Times he will formally make the announcement Friday during a speech before a meeting of the Democratic National Committee in San Francisco.
"I want to use this opportunity, with all of you here, to announce that I am ending my campaign for president," he will say, according to prepared remarks. "Though this campaign is not ending the way we hoped, I am leaving this race knowing that we raised issues that are vitally important to the American people and our future.
"I will continue to fight for a new generation of leadership in our party and our country. And most of all, I will be campaigning my [butt] off for whoever wins our nomination in 2020."
"Really, it's a debate about how far left the party should go," Moulton said.
Moulton praised Biden Friday, but stopped short of an endorsement.
'I'm not going to endorse anyone right away, but the vice president is a mentor and a friend and I think he'd make a great president," he said. "Anybody in this race will be better than Donald Trump and I will enthusiastically support whoever the nominee is."
Moulton told the Boston Globe this week Democrats will need to grow its base to beat Trump next year.
"We've got to build a broad coalition, not just Democrats, but disaffected Republicans, Obama voters," he said. "That's what I did as a platoon leader in Iraq. I had Marines from Texas, from Massachusetts, from all over. Different races, backgrounds, religions."
Moulton is up for re-election next year.