Luke Bronin, the former two-term Hartford mayor who raised $1 million to unseat a mayoral incumbent a decade ago, formally began a challenge Wednesday morning to 14-term U.S. Rep. John B. Larson for the Democratic nomination in the 1st Congressional District in 2026.

Bronin, 46, who recently tried to coax the 77-year-old Larson into retirement, made his anticipated announcement in a 90-second video posted on social media at 5:30 a.m., becoming the third and best-known challenger to an incumbent untested since winning the open seat in 1998.

“I’m running for Congress, because we have to change the way we’re doing things, and we don’t have time to wait,” Bronin said.

Sleeves rolled up and looking straight into camera, Bronin presented himself as a needed jolt of energy and purpose for a Democratic Party at a cross-roads, controlling every congressional seat in Connecticut, but struggling nationally after Donald J. Trump won a second term.

“I’ve got three kids, and I’m scared for their future and for our country, and I’m worried about our Democratic Party, too,” he said. “If we’re going to win back what we lost to Donald Trump, we need a party that makes sense to people, that’s not trying to defend the system that’s broken, but trying to fix it, a party that you’re energized and excited about because we are aggressive and clear about what we’re fighting for and who we’re fighting for.”

Bronin is a Navy veteran of Afghanistan who worked in the Obama administration and served as general counsel to former Gov. Dannel P. Malloy before winning the first of two terms as mayor of Hartford in 2015, taking control of a city government then on the verge of bankruptcy.

“As mayor, I was honest about problems and serious about fixing things. You saw me work 24/7, 365, for eight years fighting for my city every way I knew how,” Bronin said. “And that’s the kind of energy and urgency the Democratic Party needs in Congress from every single leader — not someday in the future, but right now.”

That was the essence of his initial pitch for unseating Larson: It’s time.

Bronin offered no criticism of Larson, nor did he highlight any differences in issues with the liberal congressman or mention him by name. But he essentially offered a tip of the cap to Larson and repeated a message he delivered in person to the congressman over coffee less than three weeks ago.

“I respect people who’ve served in Congress for decades, but at a certain point it’s just time to let some new voices in. Join me and let’s make the change we know we need,” Bronin said. “It’s time.”

With the help of significant state aid, Bronin succeeded in stabilizing Harford’s finances. He did not seek a third term and exited city hall in January 2024. He and his wife, Sara Bronin, have since announced a separation and intention to divorce.

After only two years in city hall, Bronin briefly ran for governor in 2018, when the seat was open. He was preparing to do so again, but opted for the congressional race after concluding Gov. Ned Lamont, a Democrat, was likely to seek a third term next year.

School board member Ruth Fortune, 37, of Hartford created a campaign committee to challenge Larson on July 3, and Councilman Jack Perry, 35, of Southington followed suit on July 22, vowing to spend $500,000 of his own money in a safe Democratic district centered on Hartford and its suburbs.

Larson, a lifelong resident of East Hartford whose political career began with election to the town’s school board in 1977, began July with $262,467 in cash on hand and the expectation of an easy summer before kicking off a promised reelection campaign in the fall.

Bronin, who grew up in Westchester, N.Y., and settled in Hartford after attending Yale as an undergraduate and law student, will not have access to all the same Hartford-area donors challenging Larson as he did in running for mayor. But his financial base is broader than Hartford County.

The early filing by Fortune was a harbinger of things to come, but Larson says he nonetheless was stunned when Bronin suggested in person it was time to pass the baton. A fourth potential challenger, state Rep. Jillian Gilchrest, D-West Hartford, has been making calls gauging support.

Democrats say a rattled Larson has been making calls shoring up support among potential delegations to a nominating convention next year. His last competitive race was the primary he won in 1998 over Secretary of the State Miles Rapoport for the seat Barbara B. Kennelly was leaving to run for governor.

Larson suffered a “complex partial seizure” that caused him to freeze and abruptly stop speaking while delivering a speech in the House of Representatives in February. He had a briefer, similar episode at a press conference in April.

Larson remains the favorite at prevailing in a nominating convention, but Bronin is capable of testing him in a primary. 

Qualifying for a primary requires winning 15% of the convention vote or gathering signatures from 2% of registered Democrats in the district.

In 2022, a former congressional aide, Muad Hrezi, failed to gather the 3,833 signatures necessary to qualify, blaming mistakes by local and state elections officials and a system he complained was stacked in favor of incumbents.