Schwartz, a Democrat, is widely expected to challenge Gov. Corbett, but has made no official announcement.
Schwartz has represented the district, in Northeast Philadelphia and part of Montgomery County, since 2004.
Leach, 51, was born in the Northeast, but now lives a block outside of the district in Upper Merion. He said he did not plan to move.
He has been considered one of the most liberal lawmakers in the GOP-controlled Assembly. He has gained national attention as the sponsor of legislation to decriminalize marijuana and legalize same-sex marriage, and has been a vocal opponent of the state's voter ID law.
Leach said that if elected to Congress, he would introduce legislation to establish a uniform national system for awarding Electoral College votes, to end what he called the Republican campaign to "cherry pick states and change the rules when it benefits them."
Beyond Leach; Valerie Arkoosh, an anesthesiologist, professor at the University of Pennsylvania Medical School, and advocate for the Affordable Care Act; and Saidel have filed statements of candidacy for the Schwartz seat with the Federal Elections Commission.
As many as eight other names are being circulated as potential candidates. Among them are those of State Reps. Mark Cohen and Brendan Boyle, both of Philadelphia, and Montgomery County Commissioner - and former State Rep. - Josh Shapiro.
Schwartz has said she has no intention of running for both her congressional seat and for governor next year. A spokeswoman said she was not endorsing a candidate in the race for her seat.
Contact Amy Worden at 717-783-2584 or email@example.com or follow @inkyamy on Twitter.