The 47-member chamber will take up the House version of the bill, which advanced from the House last week and was approved Tuesday by the Senate Judicial Proceedings Committee.
The bill narrowly passed the House, 72-67, after heated debate and last-minute switches by several lawmakers, but it is expected to receive a virtual rubber stamp in the Senate, which passed last year’s failed gay-marriage legislation by a 25-21 vote.
“When the vote was taken last year, those votes were locked in,” said Sen. Joseph M. Getty, a Carroll Republican and opponent of the bill. “I don’t see any changes.”
Gay marriage still appears to have support from 25 of 47 senators, with 24 of 35 Democrats and 1 of 12 Republicans.
The Judicial Proceedings Committee approved the bill by a 7-4 vote, identical to its tally last year.
Supporters said this year’s bill effectively protects religious institutions and faith-based groups from having to perform or condone gay marriages, and bristled at complaints that the bill doesn’t allow private residents or business owners to deny services or participation to gay couples.
“There’s really no legitimate complaint,” said Sen. Jamin B. Raskin, Montgomery Democrat. “The churches get to decide who gets married in the church hall and we get to decide who gets married in city hall.”
Supporters were also content to accept House amendments to the bill, pointing out that any Senate changes would send the bill back to the contentious House.
The amendments would delay the law’s effective date from October to January, keep it from taking effect until after any lawsuits over a referendum effort are resolved and provide that any court rulings against any portion of the law would void the law entirely.
Senate passage would give opponents the go-ahead to begin crafting a petition seeking to put the bill to a November referendum. They would have until June 30 to collect 55,736 voter signatures.
While the Senate could begin debate Wednesday, opponents may request postponement until Thursday, allowing them more time to prepare amendments.
The Senate is expected to give the bill preliminary approval after its first round of debate and final approval after a second.
If passed, the bill would make Maryland the eighth state along with the District to legalize gay marriage.
Mr. O'Malley, a Democrat, would be able to sign the bill at his earliest convenience but has not decided when he would do so, a spokesperson said Tuesday.