Corbett's support of legislation that has languished in the General Assembly for a decade is viewed by many advocates as a major step forward on a civil rights issue.
"This is remarkably big news," said Ted Martin, executive director of Equality Pennsylvania, a statewide gay rights advocacy group. "His leadership will move the issue forward in a way that is long overdue."
Currently, 23 states, including all of the Northeastern United States, and 33 Pennsylvania municipalities have nondiscrimination laws that include sexual orientation and gender identity.
Also, 23 Fortune 500 companies based in Pennsylvania have similar nondiscrimination policies.
Companion bills in the House and Senate to amend the Pennsylvania Human Relations Act were introduced this year by Rep. Dan Frankel (D., Allegheny) and Sen. Pat Browne (R., Lehigh) with bipartisan support. But both pieces of legislation have failed to move out of their respective committees.
Corbett's decision comes as his administration is locked in a federal court battle over same-sex marriage.
The American Civil Liberties Union sued the state in July on behalf of gay and lesbian plaintiffs who contend that banning marriage violates their constitutional rights.
In the midst of the debate over the legal case, Corbett inflamed gay rights supporters when he said gay marriage was the legal equivalent of marriage between a brother and a sister.
In the interview Tuesday, Corbett, citing his Catholic upbringing, said he did not see any conflict in what he views as separate issues.
"My position hasn't changed" on gay marriage, he said. "I understand other people's positions. I believe marriage is one man and one woman. But we'll let the court look at it."
The nondiscrimination bills include language that would exempt religious schools and certain businesses that have a religious affiliation.
Corbett mentioned a like-minded conservative in Congress, U.S. Sen. Pat Toomey (R., Pa.), who voted for the federal nondiscrimination bill that passed the Senate last month.
Closer to home, the move pits the governor against one of the legislature's most vocal conservatives, Rep. Daryl Metcalfe (R., Butler), chairman of the state government committee, who controls the movement of the bill in the House.
When asked how he would overcome Metcalfe's opposition, Corbett shrugged and said, "I don't know." But he added that he thought the bill, if brought to a vote, would gain support from "both sides of the aisle."
Political analyst and pollster G. Terry Madonna of Franklin and Marshall College called Corbett's support of the bill a smart political move.
"It's a significant announcement on his part, given the fact it's an important agenda item of supporters of gay equality," said Madonna, who this year released the first poll showing that a majority of Pennsylvanians supported same-sex marriage. "Even if you're not for gay marriage, who supports discrimination?"
Madonna said the support will help Corbett where he has had trouble in the past, with women voters and in the culturally more liberal southeast. But Madonna said it was too early to speculate on what it could mean for Corbett when he runs for reelection next year.