State Rep. Brian Sims, the first openly gay member of the Pennsylvania General Assembly, has made it official: he’s challenging Congressman Chaka Fattah in the Democratic primary.

Sims is the third, but arguably the highest profile, candidate to come out against Fattah for the Democratic nomination. He joins Dan Muroff, a ward leader in Northwest Philadelphia, and Lower Merion Township Commissioner Brian Gordon in the race.

“No one will fight harder for justice in the eyes of the law and respect in the minds of our leaders,” Sims said in a campaign video announcing his candidacy today.

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Fattah was indicted in July on corruption and racketeering charges. His margins of victory are among the highest of any member of Congress — though that may be attributed to the high percentage of Democrats in the district, which spans the west and northwest portions of Philadelphia and parts of Montgomery County. 

Fattah, who is serving his 11th term, has maintained his innocence. He has rejected calls for his resignation, but has stepped down from a leadership post on the House Appropriations Committee and vowed to run for re-election. 

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Sims is the son of two Lieutenant Colonels in the Army played high school football at Downingtown High School and college ball at Bloomsburg. He went on to law school and became a civil rights attorney before challenging Democratic State Rep. Babette Josephs for her seat. 

Fattah is the son of civil rights activists who served as a state representative and then state senator before being elected to Congress in 1994. He made a failed run for mayor in 2007. That race — and the difficulty he had raising money during the campaign — was the source of some of the allegations in the federal indictment against him. 

Franklin and Marshall College professor Terry Madonna said the charges against Fattah don't necessarily rule out a successful re-election. It's happened before in the state. 

He told Metro on Tuesday that Sims has an uphill battle because Fattah maintains a significant amount of goodwill.

"He's been around a long time and he's done a lot of favors for a lot of people," Madonna said.