Sen. Sherrod Brown, an Ohio Democrat who almost ran for president but sat out in hopes that someone else would adopt his “dignity of work” message, got a little validation last month.

A proposed trade deal involving the US, Mexico, and Canada — known as USMCA — had just passed the House, after Brown helped negotiate new language that would make it friendlier to organized labor. At a presidential debate that night, two senators on stage were asked if they would vote for it.

Bernie Sanders of Vermont went first, and though he alluded to the changes Brown had won — “a modest improvement” — he was a hard no. Next came Amy Klobuchar of Minnesota, who basically said if it was good enough for Brown, it was good enough for her.

“I'll go with my friend, Sherrod Brown,” said Klobuchar, who noted that Brown has voted against every trade deal that has come up during his time in Washington. “He's voting for this, and I am, too.”

The moderate Klobuchar’s shoutout was a virtue signal to the left. Brown’s opposition to NAFTA, the North American Free Trade Agreement that USMCA would replace, is the signature issue of his career. And even from the sidelines, he remains an influential force on labor and trade.

The provisions advanced by Brown and Sen. Ron Wyden, an Oregon Democrat, aim to make it easier for Mexican workers to unionize and collectively bargain. The US would monitor Mexico’s compliance, have the ability to quickly respond to reported violations, and have the option to block imports made in plants with repeated violations.

“If Mexican workers do better, two things happen,” Brown said in a telephone interview Thursday. “One, American companies are less likely to move there. … Second, it means Mexican workers will have more buying power and be able to buy American products.”

Brown told BuzzFeed News he didn’t watch last month’s debate but quickly learned about Klobuchar’s credit from his brother. As pleased as he was, Brown said he wasn’t surprised to learn that another Democrat from the industrial Midwest agreed with him. He also name-checked Sanders and another senator in the race, Elizabeth Warren of Massachusetts.

“Warren understands it,” Brown said. “Sanders understands it.”

Warren has said she will vote for the USCMA, citing the provisions Brown negotiated.

Sanders remains skeptical. He and Brown long have been known as two of the most liberal members of Congress. They jumped from the House to the Senate in 2006 with mutual populist and progressive ideals. But the 2020 election has brought a slight ideological split between old friends. (In another contrast, Brown, during his travels last year to suss out the possibility of a presidential bid, came out against the Sanders-backed Medicare for All.)

“It would allow, hopefully, Mexican workers to organize into unions, independent unions, and be able to negotiate decent contracts,” Sanders said of the USMCA deal when it came up at the debate.

“But at the end of the day, in my view, it is not going to stop outsourcing. It is not going to stop corporations from moving to Mexico, where manufacturing workers make less than $2 an hour.”

Brown on Thursday attributed Sanders’ continued opposition to presidential politics.

“Bernie’s going to make his decisions based on a lot of things,” he said. “I did not talk to him about it. We’ve worked on these issues. We worked against NAFTA together; we worked against PNTR together, with China. But I did not personally try to persuade him. When you run for president, your decisions are made all kinds of ways. I don’t interfere with that. I know we will have the votes in big numbers to pass the Senate, and I’m happy with that.”

He added that he does not doubt Sanders’ commitment to workers. “I think Bernie’s position on trade through his whole career will help him if he’s the general election candidate. It’s not like he’s against the labor stuff. He just thought there should have been other stuff, too."

Brown has no immediate plans to endorse a candidate — “possibly in early March or February” — but said he hears “pretty often” from candidates hoping for his support.

“I don’t want to talk about who’s called me and who hasn’t and what we’ve said,” Brown said. “I just don’t think that’s fair.”