Pennsylvania's first openly gay elected state lawmaker is challenging a longtime Philadelphia congressman who's vowing to remain in office while fighting corruption charges.

State Rep. Brian Sims on Tuesday announced he's running to unseat 11-term U.S. Rep. Chaka Fattah.

He's the third person to challenge the 58-year-old Fattah in next year's Democrat primary.

The 37-year-old Sims has been a state legislator since 2013. He's fought for marriage equality, pay equity and a conversion therapy ban.

He's also a lawyer and a former college football player.

City ward leader Dan Muroff and Lower Merion Township Commissioner Brian Gordon are also running against Fattah.

Fattah has denied charges he paid off an illegal $1 million campaign loan with federal grants and charitable donations, and funneled campaign funds toward his son's student loan.

Fattah is married to NBC10 News anchor Renee Chenault-Fattah, who is currently on leave from NBC10.