Brian Sims on Tuesday was sworn in as a member of the Pennsylvania House, becoming the state's first openly gay elected lawmaker.

The 34-year-old Sims, a policy attorney and civil rights advocate, won his Democratic primary, unseating longtime incumbent Rep. Babette Josephs of Philadelphia, and ran unopposed in the November election.

“The tide has changed,” Sims told The Philadelphia Inquire. “2012 will go down in history as when being anti-gay puts you in the minority.”

While Democrats in November narrowed the Republican majority in the Senate, the GOP remains in control of both chambers. Among the issues expected to be addressed in the legislative session is a constitutional amendment limiting marriage to heterosexual couples.

In December, Republican Rep. Daryl Metcalfe announced plans to reintroduce a resolution that seeks to ban gay marriage in the state.

“This constitutional amendment will eliminate confusion as to what constitutes a legal marriage, and it will also designate marriage as the only type of union that will be legally recognized in Pennsylvania,” Metcalfe said in a press release.

Rep. Mike Fleck, a sitting Republican from Huntingdon County, recently announced he's gay, making Sims the House's second openly gay member.

(Related: Mike Fleck, Republican Pennsylvania state rep., comes out gay.)