Beto O’Rourke is the latest entry into the race for the Democratic presidential nomination.

But the former three-term congressman from Texas surely won’t be the last.

BETO O'ROURKE JUMPS INTO 2020 RACE WITH EARLY MORNING ANNOUNCEMENT

O’Rourke – who came close to defeating Republican Sen. Ted Cruz in last year’s midterm elections – on Thursday morning become the 15th major Democrat to announce a candidacy or form a presidential exploratory committee.

Here’s a look at who's still on the fence, and could come next:

Former Vice President Joe Biden

The former vice president earlier this week dropped his clearest hint yet that he’s all but certain to launch what would be his third White House bid.

Biden was greeted with chants of “run Joe, run” as he took the podium Tuesday in Washington, D.C. at the annual convention of the International Association of Fire Fighters union. Many in the crowd also were waving ‘Run, Joe, Run,’ and ‘Fire Fighters for Biden’ signs.

A few minutes later, during his keynote address, Biden said: “I appreciate the energy you showed when I got up here. Save it a little longer. I may need it in a few weeks.”

Sources familiar with the planning of Biden’s inner circle last week confirmed to Fox News that top advisers to the former vice president are getting their ducks in a row, figuring out a campaign structure and reaching out to veteran Democratic operatives who would be involved. Those sources pointed to a likely April campaign launch.

Sen. Michael Bennet of Colorado

During a jam-packed trip last week to New Hampshire – the state that holds the first primary in the race for the White House – the two-term senator told Fox News that his decision would come in “weeks, not months.”

“I need know there’s a real opportunity for me to make a difference in the race and that I could have a chance to win the race. That’s what I’m trying to figure out,” Bennet explained.

But he added that “I’m inclined to do it.”

Gov. Steve Bullock of Montana

The two-term governor returns to New Hampshire next week. And last month he stopped in Iowa, which votes first in the presidential caucus and primary calendar.

While visits to the early-voting states aren’t a guarantee a potential contender will actually jump into the race – think Sen. Sherrod Brown of Ohio, who recently passed on a White House run after trips to all four of the states that vote first in the nominating calendar – Bullock made a clear signal of his intent with the recent hiring of a veteran Democratic political operative.

Bullock’s said he likely will not make any public announcements about his 2020 intentions until after Montana’s legislative session concludes in April.

New York City Mayor Bill de Blasio

De Blasio heads to New Hampshire this weekend, fueling speculation that the two-term progressive mayor of America’s largest city is seriously considering a bid for the Democratic presidential nomination.

The trip follows a visit last month to Iowa, the state that votes first in the presidential caucus and primary calendar. And last weekend, de Blasio and his wife traveled to South Carolina, the state that holds the first southern primary along the road to the White House.

Last month, the mayor told New York City reporters “I’m not ruling it out” when asked about his 2020 intentions.

Rep. Eric Swalwell of California

The congressman from the East Bay Area has also made multiple trips to the early-voting states. He recently headlined ‘Politics and Eggs,’ a must stop in New Hampshire for White House hopefuls.

Swalwell’s hired staff in Iowa and is in the process of making hires in New Hampshire and South Carolina.

“I see nothing but green lights so far,” he told Fox News earlier this year.

Rep. Seth Moulton of Massachusetts

The congressman from the north shore of Massachusetts, a U.S. Marine veteran who served four tours of duty in Iraq, is headed to New Hampshire this weekend. And he’ll travel to Iowa later this month.

Moulton, who was one of the ringleaders of the faction of House Democrats who unsuccessfully tried to prevent Nancy Pelosi from returning to the speakership, has said he’s taking “a very hard look” at launching a presidential campaign.

Rep. Tim Ryan of Ohio

The longtime congressman from northeast Ohio – who like Moulton was another leader of the anti-Pelosi House Democratic faction – has also been making the rounds in the early-voting states.

Ryan, during a stop last month in New Hampshire, told Fox News: “I think there’s plenty of time to get to know people in Iowa and New Hampshire and the early states and raise the kind of money that you would need. I think you’ve got to make a decision soon, but I’m not feeling like we missed the opportunity.”

Stacey Abrams

Stacey Abrams, a rising star in the Democratic Party who narrowly lost last November's gubernatorial election in Georgia, said Monday it was possible she could seek her party's presidential nomination next year.

The former Georgia House minority leader made her comments at the South by Southwest conference and festival in Austin, Texas.

Former Gov. Terry McAuliffe of Virginia

The former Virginia governor -- who steered the Democratic Party in the early 2000’s and remains a top friend and adviser to Bill and Hillary Clinton -- has said he would decide on whether to launch a 2020 White House campaign by the end of March.

But if Biden enters the race, McAuliffe might be more inclined to pass on a presidential bid.

Asked whether he was waiting for the former vice president to make his own 2020 decision, McAuliffe told CBS News last month that he wasn’t, but added he "wants to see where the field is."