PROVIDENCE, R.I. (WPRI) — More progressive leaders on Capitol Hill are coalescing around the candidacy of former state Rep. Aaron Regunberg for Rhode Island’s open congressional seat.

The Congressional Progressive Caucus PAC — the political arm of the legislative bloc with the same name — announced Tuesday its endorsement of Regunberg in the Sept. 5 primary to succeed David Cicilline. He is one of 12 Democrats vying for the party’s nomination.

“Aaron Regunberg has dedicated his life to promoting the common good and taking on special interests and it is critical that Congressman David Cicilline’s successor has the record and values necessary to build on his substantial progressive legacy,” PAC co-chairs Mark Pocan, Pramila Jayapal and Jamie Raskin said in a joint statement.

“Like David, Aaron has direct experience overcoming gridlock and corruption to stand up to corporate power and win real progress,” they said. (Cicilline held a leadership role in the Congressional Progressive Caucus during his time in the House.)

The PAC’s announcement is the latest in a drumbeat of endorsements rolled out by Regunberg’s campaign as he seeks to position himself as the best choice for left-leaning voters in the 1st Congressional District. Raskin headlined a fundraiser for him in Newport last month.

“People sometimes ask me what progressive means,” Regunberg said in a statement. “My answer: being progressive means fighting for a government and an economy that works for everyday people, not just big corporations and wealthy campaign donors.”

The congressional primary is suddenly in flux after Lt. Gov. Sabina Matos, the race’s widely acknowledged frontrunner, suffered a week of bad headlines when it emerged her campaign had submitted forged signatures on ballot paperwork. Attorney General Peter Neronha is conducting a criminal investigation into the matter.

While no reliable independent polling has been released in the 1st District primary, Regunberg is among Matos’s strongest challengers, in part due to residual name recognition from his near-miss 2018 bid for lieutenant governor. He raised more money than any other candidate during the second quarter.

Other leading candidates for the 1st District seat include former White House official Gabe Amo, Jamestown investor and academic Don Carlson, and state Sen. Sandra Cano. Matos and Amo are both hitting the airwaves on Tuesday with their first TV campaign ads, and 10 of the candidates met for a forum held Monday night.

The other seven candidates are state Sen. Ana Quezada, state Rep. Steve Casey, Providence City Councilor John Goncalves, U.S. Navy veteran Walter Berbrick, former state Rep. Spencer Dickinson, second-time candidate Stephanie Beauté and Republican-turned-Democrat Allen Waters.

Early voting starts Aug. 16.

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 Threads, Twitter and Facebook.