With at least 15 candidates who currently or previously served in Congress, most Democrats are letting the race take shape and sort itself out before they jump on board.
"I have too many friends in there," Rep. John Lewis, D-Ga., said Friday, adding he has no plans to endorse anytime soon. "It's too early, just too early."
Just nine senators and 45 representatives - fewer than 20% of all Democrats in Congress - have formally endorsed one of the presidential candidates, according to a comprehensive "2020 Endorsement Primary" analysis by FiveThirtyEight, a politics and sports data website.
By contrast, in April 2015, Hillary Clinton had already locked down more than 200 Democratic lawmakers for her 2016 presidential bid against a much smaller field, with Sen. Bernie Sanders, I-Vt., emerging as the only real primary challenger.
Not surprisingly former Vice President Joe Biden, who spent 36 years as a senator, has emerged as front-runner among congressional Democrats: five senators and nine members of the House have endorsed his campaign.
Beyond Biden's support, the other senators to back a 2020 candidate are the home-state colleagues of Sens. Cory Booker, D-N.J., Amy Klobuchar, D-Minn., Elizabeth Warren, D-Mass., and Sanders.
To be sure, endorsements do not carry the same weight as they used to, particularly now that members of Congress cannot vote as "superdelegates" at the Democratic National Convention unless there is no clear nominee on the first ballot at the July 2020 gathering in Milwaukee. And the power of local party machines has been diluted by the 21st century political superhighway of information for voters from social media and 24/7 cable news.
"There are probably a select few people in public life whose endorsement can be very consequential," said Rep. Joe Kennedy, D-Mass., who was one four members of the Massachusetts delegation to endorse Warren.
Kennedy's great uncle, the late Edward Kennedy, served that role in 2004 and 2008, throwing his enormous clout behind John Kerry and Barack Obama, helping each senator go on to win the Democratic nomination.
Today, aside from Obama, who is remaining neutral, few Democrats hold that sort of sway. Still, endorsements are like health insurance - you really don't want to rely on them, but it's better to have them than not at all.
Lewis, the famed civil rights leader, is one of those sought-after endorsements for 2020 contenders. "Oh, there's several candidates that have been by to see me, several. Sat on my sofa in my office," he said.
Another liberal star, Rep. Alexandria Ocasio-Cortez, D-N.Y., is surveying the contenders to see which will embrace her bold agenda. "Right now I am looking for specific policy commitments coming from 2020 candidates," said the first-term firebrand, who worked for Sanders in 2016.
Aside from home-state support, presidential contenders have been eyeing Democrats in the early nominating states of Iowa, New Hampshire and South Carolina. The courtship is sometimes subtle, sometimes blunt and often involves just listening.
"Nearly all of the candidates have reached out at some point or another," Rep. Joe Cunningham, D-S.C., said Friday.
Cunningham, who won an upset victory in 2018 in a Republican-leaning district in the state's southeast corner, is pushing local issues to this group of people who might produce the next president.
"We're just trying to use this as an opportunity to showcase what the issues are for the Low Country and the 1st Congressional District, and how important our beaches are, our natural resources, and stress the need for an infrastructure plan," he said.
Rep. Cindy Axne (D), who won a GOP district last fall, regularly hears from 2020 candidates when they visit her southwestern Iowa district, according to an adviser.
But like most freshmen, from Ocasio-Cortez on the left to Cunningham in the center, Axne has no plans to endorse at this stage.
A trio from the Philadelphia suburbs - Reps. Madeleine Dean, Chrissy Houlahan and Mary Gay Scanlon - attended Biden's kickoff fundraiser last month in that city, but none of the three first-term Democrats has formally endorsed their neighbor from Delaware.
"I thought it was very cool that on his first day he wanted to be in Philadelphia. We are going to be the 'Keystone State' again," said Dean. "The other thing that's really cool is look at how many women are running."
Rep. Mikie Sherrill, D-N.J., is the rare member of the class of 2018 to endorse. A former federal prosecutor based in Newark, Sherrill has worked with Booker for more than a decade on criminal justice issues.
"I knew him when he was Mayor Booker," she said.
New Jersey is the only state that is operating under the old-school ethos of supporting its favorite son.
All 12 New Jersey Democrats on Capitol Hill unified behind Booker, breaking from past presidential campaigns when bad blood developed.
"Typically Jersey folks go 30 different ways," Rep. Bill Pascrell Jr. (D-N.J.) recalled Friday. In 2008, Pascrell joined most state Democrats supporting Clinton in the presidential primary, while a smaller group backed Obama.
New Jersey Democrats want to stay as a bloc again should Booker fade from the race, Pascrell said. "If we keep everybody together now, for our home brother, that will be easier if we need to move later on."
Some endorsements don't grab headlines, but might pay real dividends. Take Rep. Dwight Evans, D-Pa.
The second-term Evans never served in Washington with Biden, but his supporters are ecstatic Evans came on board. Evans has a political machine in north and west Philadelphia, having previously represented the area for 36 previous years in the state House.
He made the decision without talking to Biden, just his own insights gained from decades of studying who can win Pennsylvania. "He has the best shot," Evans said.
Ultimately, of course, it's up to the candidates to win the votes.
"It's on every candidate to go out there and put their values and visions forward to the country," Kennedy said. "And I don't think the country is waiting to see who wins an endorsement game amongst members of Congress."
Sign up for the daily JWR update. It's free. Just click here.