BALTIMORE — One of Bernie Sanders’s few prominent supporters on Capitol Hill is promising that reinforcements are coming for the Vermont senator’s insurgent campaign for the Democratic presidential nomination.

Rep. Keith Ellison (D-Minn.), one of just two Democrats in Congress to endorse Sanders, said that at least two more lawmakers were on the verge of publicly backing the 74-year-old senator and that more were waiting to see if he would actually defeat Hillary Clinton in Iowa next week or New Hampshire the following week.

Rep. Keith Ellison (D-Minn.), speaking on Capitol Hill in 2011. (Alex Brandon/AP)

“No politician wants to support a campaign, no matter how noble and good, that isn’t viable. And as Bernie demonstrates some true viability, which he’s doing now, he’ll get more support. No doubt about it,” Ellison said in an interview here Thursday, taking a break from the three-day retreat of House Democrats to Charm City to map out their own 2016 strategy.

Ellison said he and Rep. Raul Grijalva (D-Ariz.), the other supporter of Sanders, fielded questions and comments from colleagues throughout the retreat and in recent weeks, some with a modest level of intrigue and others with increasing interest in how he had tapped the energy of young liberal activists. Ellison spent Tuesday with Sanders in Minnesota, where he drew 15,000 supporters to St. Paul and then 6,000 to Duluth, the sort of turnouts usually associated with major hockey games in those places and not politics.

“A lot of people were, like, wow, this is pretty significant,” Ellison said of lawmaker reactions this week.

He stressed that there would not be a wholesale shift of supporters away from Clinton to Sanders, but guaranteed that two lawmakers “are inclined to come out for Bernie soon, but I’ve talked to many people who like Bernie and are complimentary.” The more success Sanders has beyond the first two states, the more he can persuade the last several dozen Democrats in Congress who have not yet indicated their support for Clinton.

According to a tally kept by The Hill, 148 of the 188 members of the House Democratic caucus are supporting Clinton, with 38 of the 46 members of the Senate caucus backing the former secretary of state.

But Sanders has touched a nerve with the most liberal activists, and Democratic leaders are treading carefully around his campaign for fear of antagonizing those voters whom they will need in the fall. House Minority Leader Nancy Pelosi (D-Calif.) fell off her usual script Wednesday when she dismissed portions of Sanders’s agenda, including his calls for higher taxes in order to finance a broad rewrite of health laws to essentially replace the 2010 Affordable Care Act.

“We’re not running on any platform of raising taxes,” Pelosi told reporters inside the Hyatt Regency in Baltimore’s Inner Harbor on Wednesday.

[Pelosi dismisses portions of Sanders’s agenda]

By Friday morning, at the news conference concluding the retreat, Pelosi returned to her normal posture of praising Sanders for energizing what had previously been a fairly sleepy Democratic nominating race. “I’m very proud of the way Senator Sanders has expanded the universe of young people, especially, interested in the political process,” she told reporters, focusing on his attacks on unlimited and undisclosed contributions by billionaires. “I think history will record that Bernie Sanders’s candidacy had a very wholesome effect on our political process.”

Ellison said he’s plugged in to the top level of the Sanders team, frequently talking with Jeff Weaver, the campaign manager, and Robert Becker, who is running the Iowa caucus operation. He said that he has fairly open access to the candidate.

“I can call Bernie. You wanna talk to Bernie? I can get him on the phone now, if he’s not speaking. If he’s not busy, I can talk to him,” Ellison said during the interview. [Disclosure: Despite prodding to call Sanders, Ellison declined the suggestion from The Washington Post.]

He and Grijalva are not putting on a hard sell at this point, instead letting members do most of the talking.

“There are a number who are thinking: ‘Well, you know, I like this thing, I might come in, who do I talk to, how can I be more involved, or I think Bernie needs to do this, or I can’t come out but I’m definitely open.’ So there’s that kind of conversation happening, constantly,” Ellison said.