It used to be that Bernie Sanders was an ideological lone ranger in the Senate. Now, a whole host of potential presidential hopefuls are racing to represent the liberal grass roots on their issues of the day — and pulling the Democratic Party’s center of gravity further to the left.

The trend was apparent throughout the fall among the half-dozen Democratic senators drawing the loudest buzz for 2020 — aside from Sanders (I-Vt.), the group includes Sens. Kirsten Gillibrand (D-N.Y.), Kamala Harris (D-Calif.), Cory Booker (D-N.J.), Elizabeth Warren (D-Mass.) and Jeff Merkley (D-Ore.).


First they flocked to Sanders’ single-payer health care proposal. And then, almost in unison, they adopted two other stands popular among the Democratic base: Refusing to vote for any budget plan that didn’t include help for undocumented immigrants brought to the country as children, and calling for Donald Trump’s resignation over sexual harassment claims leveled against him last year by multiple women.

The six Democrats also have been the most frequent foes of Trump’s nominees earlier this year.

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The clustering could make for a crowded lane of very progressive candidates in 2020, a space that Sanders had virtually to himself in 2020. And if the trend continues and extends to other topics and candidates, it could allow Trump to more easily attack his reelection opponents as puppets of the activist left.

But those worries are secondary in the rush to take on the unpopular president.

Part of the reason the six liberal Democrats have moved so fast on debates that capture the anti-Trump zeitgeist is the current era’s emphasis on “rewarding authenticity,” said Adam Green, co-founder of the liberal group Progressive Change Campaign Committee and a leading organizer around the single-payer health care push.

As Democrats strive to get beyond talking points and connect with voters ahead of 2018 and 2020, Green said, that creates “an incentive to be first out of the gate on high-profile issues.”

“There’s no doubt that [potential] presidential candidates piling onto the Medicare-for-all bill gave it legs and a sense of momentum that allowed others to feel comfortable adding their voices as well,” Green added in an interview.

Indeed, single-payer health care was this fall’s first unity showcase for the six Democrats. In fairness, while “Medicare for all” is primarily associated with Sanders (I-Vt.), Gillibrand backed a Medicare buy-in as long ago as her first 2006 race for the House, and Merkley is also a longtime supporter.

Those two were on board Sanders single-payer bill even before he rolled it out in September. Harris, Booker and Warren also were early supporters.

Democratic leaders in both chambers withheld their support from the single-payer bill, but the presence of those big names helped the legislation net endorsements from one-third of the party’s Senate caucus.

A similar calculus played out last month as activists demanded that Democrats use their leverage on a must-pass year-end spending bill to secure help for the young undocumented immigrants known as Dreamers. And the same six senators were the first to vow that they couldn’t support any government funding bill without deportation protections for Dreamers — paving the way for two-thirds of the Democratic Caucus to withhold their votes from that legislation on Dec. 21.

When a sexual misconduct scandal took down one of their own, Sen. Al Franken (D-Minn.), among the first Democratic senators to push back with calls for Trump to step down over his own alleged impropriety with women were Merkley, Sanders, Gillibrand, Harris and Booker. (Warren did not publicly call for Trump’s resignation.)

“On each of those issues, I feel very strongly about the importance of being a voice that reflects the voice of California,” Harris said in an interview after joining most of her fellow Democratic senators in opposing the government funding legislation.

Though none of the six Senate Democrats cited has formally declared intentions for 2020, each is on the list of potential candidates. And all six — particularly Warren and Sanders, who also have seats at Senate Minority Leader Chuck Schumer's (D-N.Y.) leadership table — are poised to play an even bigger role in shaping the party's agenda ahead of the 2018 midterms.

The first major test of the bellwether liberals' ability to push their party along may come as soon as January, when Senate Majority Leader Mitch McConnell (R-Ky.) has said he would allow a floor vote on an immigration deal that includes protections for Dreamers if bipartisan negotiators can reach one. Immigration advocates are wary of being forced to swallow any compromise that includes aggressive new enforcement measures, however, which could exert heightened pressure on the six liberal senators who have aligned most closely with their cause.

But for the time being, activists like Angel Padilla, policy director of the liberal group Indivisible, are thrilled to see big-name Democratic senators taking up the Dreamers' banner after years of seeing immigration treated warily by party leaders.

"It’s important to have the left flank of the Democratic party talking about this for a number of reasons," Padilla said in an interview.

Padilla pointed to the prominent role that minority voters played in Sen.-elect Doug Jones' (D-Ala.) victory this month, as well as Democrats' 2017 dominance in Virginia, where strong Hispanic turnout helped Democrat Ralph Northam win the governor’s race.