Another longtime politician is calling it quits.

Bill Keller, a member of Pennsylvania's House of Representatives since 1993, announced Friday that he is not running for reelection.

The South Philadelphia Democrat is best known for being a vocal proponent of upgrading the city's port and dredging the Delaware River. A former longshoreman, he is a close ally to John "Johnny Doc" Dougherty, the powerful leader of the city's building trades unions.

"I fought all of my career for the Port of Philadelphia and am delighted to see its long-held promise finally being fulfilled," Keller said in a statement. "I am proud to have played a role in caring for our senior citizens and providing them safe, affordable housing in the only neighborhoods they've ever known."

Keller, 67, said he feels that he has "much more to give" to the city, but that "it's time to step aside and allow the next generation to lead."

Some political insiders worry that Philadelphia will lose more clout in Harrisburg when Keller, the ranking Democrat on the House Transportation Committee, leaves office. His resignation comes as power in the Capitol, even among Democrats, is increasingly centered outside the city.

But like many elected officials nationwide who have recently announced that they are not seeking reelection, Keller faced a potentially challenging race in 2018. At least four Democrats had launched campaigns against him: Elizabeth Fiedler, a former WHYY reporter; Tom Wyatt, a Dilworth Paxson lawyer; Bill Ciancaglini, a defense attorney; and Nicholas DiDonato Jr., a retired police detective.

According to campaign finance reports filed this month, Fiedler has raised more than $53,000, while Wyatt has raised about $27,000.

Keller's office was raided by the FBI in 2010. In 2013, his business partner pleaded guilty to filing false tax returns. Keller was never charged with any crimes.

Keller's 184th District includes several rapidly gentrifying areas, including the Pennsport and East Passyunk Crossing neighborhoods. Some observers speculated that the changing makeup of the area could make Keller, a decades-long politician with strong ties to the Democratic machine, vulnerable to progressive newcomers.

District Attorney Larry Krasner won several parts of the 184th District, while a candidate supported by Dougherty finished behind him.

Keller referenced his district's shift in his announcement Friday, claiming responsibility for an upswing. "I take pride in transforming a modest, working-class district into one of the most desirable neighborhoods in Philadelphia," he said.

Keller also said that his resignation shouldn't be seen as retirement. He said he plans to work "to support and elect politicians who care as much about our community and its future as I do."

Asked if Keller had anyone in mind to succeed him, a spokesman for Keller did not immediately respond. Rumors have swirled in recent weeks that Keller's allies have begun recruiting efforts in the district in anticipation of Friday's announcement. One of those potential contenders, State Sen. Larry Farnese's aide Jonathan Rowan, said Friday that he is running for the office.