PROVIDENCE, R.I. (WPRI) — Retiring Congressman Jim Langevin came off the sidelines in the campaign to replace him Thursday, throwing his support behind Democratic frontrunner Seth Magaziner after a new poll showed Republicans positioned to flip his district.

“We simply cannot take a chance on letting Republicans win this seat,” Langevin said at a news conference Thursday afternoon as Magaziner stood beside him.

“Our party must unite behind the strongest candidate in the race,” he said. “Just as you’ve trusted me these last 22 years, I’m asking you to trust me now — that Seth Magaziner is the best candidate to continue what we started together all those years ago.”

While Langevin’s party has held the 2nd Congressional District seat since 1991, Langevin warned fellow Democrats that it could go into the GOP column this fall, providing another vote for Kevin McCarthy to become House speaker.

“Clearly Allan Fung is going to vote for Kevin McCarthy, the Republican speaker, and Seth will vote for the Democratic speaker — whether that’s Nancy Pelosi or someone else I don’t know,” he said.

“To vote for a conservative speaker means that the most conservative things, the most right-wing things, are the things that are going to come up for a vote because that’s the agenda and decides what bills to put on the floor,” he said.

(Magaziner and Langevin share more than their party affiliation: Magaziner’s chief of staff in the general treasurer’s office, veteran operative Seth Klaiman, previously served in the same role for Langevin. He was on hand for the endorsement event Thursday.)

Langevin’s decision to intervene in the primary comes as Democrats in Rhode Island and Washington are increasingly fearful that the party could lose his blue-state seat amid a national Republican wave this fall. A Boston Globe/Suffolk University poll out this week shows Fung leading Magaziner, 45% to 39%.

The new poll numbers spurred multiple Capitol Hill forecasters to shift their ratings on the 2nd District race in Republicans’ favor.

“I’m glad that it’s waking people up to the fact that we’ve got to work like hell to hold this seat,” Magaziner said.

But Magaziner doesn’t have a clear path to his party’s nomination. Multiple Democrats are challenging him in the Sept. 13 Democratic primary, though polls have shown he has a big lead over them all.

“The Democratic candidates in this race are all good candidates,” Langevin said. “But in the category of good/better/best, Seth Magaziner is the best candidate in the race.”

Langevin’s decision to endorse Magaziner was a particular blow to Democratic candidate Joy Fox, his former communications director. Still, she indicated she had no plans to quit the race.

“From the beginning, I have believed that I am the most competitive Democrat, and hundreds of hours spent talking to voters has only reinforced that view,” Fox said in a statement. “I appreciate the congressman’s service, but obviously I find his decision disappointing,” she added.

Also expressing disappointment was Refugee Dream Center founder Omar Bah, another Democratic candidate, who said he considered Langevin “a friend” after serving on his congressional diversity committee for years.

“We went with the ‘safe’ candidate in 2016 and we got Donald Trump,” Bah said in a statement. “To keep this seat, Democrats need to be bold, and need to nominate a bold, qualified candidate – and I don’t mean ‘qualified’ in the conventional sense.”

Langevin and Magaziner held their news conference one day after Fung’s only major opponent for his party’s nomination, former state Rep. Bob Lancia, bowed out of the Republican primary. The state GOP endorsed Fung for the seat at its convention on Wednesday evening.

“It’s been well over 30 years since we’ve had a Republican in this office,” Fung told 12 News. “As we’ve seen from that Boston Globe poll, I’ve got a very strong shot.”

Indeed, even Langevin described Fung as “a nice guy” on Thursday, saying, “I consider him a friend.” But he argued the Democratic Party’s policies are a better fit for the 2nd District than the Republican Party’s.

“I’m sure that Seth’s Republican opponent wants to make sure [2nd District residents] vote on personalities and not on positions,” Langevin said. “It’s going to be Seth’s job to get out there … the sharp, sharp contrast between what Seth Magaziner stands for and what Allan Fung stands for.”

Magaziner ticked off a series of issues where he disagrees with Fung, such as putting more limits on guns, keeping Social Security and Medicare as is, retaining the Affordable Care Act, and codifying abortion rights in federal law.

He said, “I’m running because I want to make sure our democracy endures for another generation, because Kevin McCarthy, Donald Trump and the far right in Washington have become radicalized, and they will do anything they can to win elections even if it means undermining our democratic process.”

For his part, Fung described the recent testimony of a former Trump White House aide about the Jan. 6 riot as “shocking,” and said he will continue to monitor the information uncovered by the House hearings.

On how Congress should respond to the Supreme Court’s decision to overturn Roe v. Wade, Fung said, “I’m not going to take any votes to ban abortions, and I want Rhode Islanders to know that. … I don’t support late-term abortions unless it’s for the life of the mother, or rape and incest.”

At the same time, Fung said a different set of issues are the ones he is hearing about most on the campaign trail.

“I’ve been out there talking to, not just Republicans, but Democrats, independents, Green Party, moderates — and everyone has basically been shellshocked by these policies coming out of Washington, D.C., that are impacting them,” he said.

“It’s basically a crisis, a cost of living crisis, because our pays are not keeping up with what is going and what we’re seeing at our retail stores, at our restaurants, at the gas pumps,” he said. “This is why everyone is so frustrated.” He said the federal government needs to spur more domestic energy production.

Magaziner said he welcomes an exchange on all the issues. “His whole campaign strategy is to hope that people don’t know what his positions are,” Magaziner said. “That is not a winning strategy. Our strategy is to make sure that voters are educated, that they know what our positions are, what his positions are, and the difference between the two.”

He added, “I want to have 20 debates with him.”

Ted Nesi (tnesi@wpri.com) is a Target 12 investigative reporter and 12 News politics/business editor. He co-hosts Newsmakers and writes Nesi’s Notes on Saturdays. Connect with him on Twitter and Facebook

Chelsea Jones contributed to this report.