Maryland House of Delegates member Tiffany Alston (D-Prince George’s County), one of two lawmakers who failed to show up for an expected committee vote Tuesday on a same-sex marriage bill, said she is now ready to vote on the bill, raising hope among supporters that the legislation would be approved by the committee late this week.

But Del. Jill Carter (D-Baltimore City), who joined Alston in boycotting the marriage bill vote as a means of promoting at least two unrelated bills stalled in the legislature, continued to withhold her vote on the marriage measure as of late Wednesday. Her action drew attention to the fragile coalition of lawmakers that LGBT advocates must rely on to enact same-sex marriage in Maryland.

Carter and Alston stunned backers of the Civil Marriage Protection Act on Tuesday morning by staying away from a meeting of the House Judiciary Committee in which a vote on the marriage bill was scheduled to take place, and announced they would not vote on the measure until Democratic leaders pay more attention to other issues they feel are equally important.

Both Carter and Alston are co-sponsors of the marriage bill. And due to the close division of committee members on the bill, their votes are needed to secure the committee’s approval of the bill to enable it to reach the House floor for a final vote.

Carter told the Baltimore Sun that Alston joined her in staying away from what had been expected to be a committee vote in favor of the same-sex marriage bill as a means of gaining “leverage” for other, unrelated issues such as restoring proposed cuts in school funding in their respective districts.

Backers of the Civil Marriage Protection Act have only enough support on the committee to pass the bill by a one-vote margin. Carter noted that it’s still relatively early in the legislative session and other bills, in addition to the marriage bill, should be placed on the fast track.

Meanwhile, Gov. Martin O’Malley reiterated his support on Tuesday for the marriage bill, repeating his commitment to sign it if it reaches his desk.

“The governor has committed to signing the bill,” said O’Malley spokesperson Shaun Adamec. “His personal support is for full equality for same-sex couples as is enjoyed by heterosexual couples. Regardless of the label the General Assembly puts on it, the governor’s objective is to achieve equality.”

Adamec said that O’Malley has been involved in lobbying for the marriage bill and has “made phone calls in support of the bill.” O’Malley has stopped short of saying he supports marriage equality. His lieutenant governor and attorney general have both publicly endorsed full marriage rights for same-sex couples.

Del. Joseph Vallario (D-Prince George’s County), chair of the House Judiciary Committee, responded to Carter and Alston’s ’protest’ action by rescheduling the vote on the marriage bill for later in the day on Tuesday, after the committee held a public hearing on as many as 16 other bills.

But at the end of the committee’s session, Carter made it known she was not ready to vote for the bill, even though she said she supports it. Vallario said he would assess the situation on Wednesday to determine when to schedule a vote on the marriage measure.

Del. Luke Clippinger (D-Baltimore City), a member of the committee who is gay, said Wednesday that Vallario tentatively set a committee voting session for Thursday afternoon. However, Clippinger said it was unclear whether the voting session would take place since Carter had yet to say whether she would attend.

Supporters of the marriage bill, which passed in the Maryland Senate last week, initially planned to hold off on a vote in the House until toward the end of the legislative session in April. But they moved up the vote to this week after determining a furious campaign against it by opponents might lead to the erosion of support.

Sen. Richard Madaleno (D-Montgomery County), the bill’s author and lead sponsor in the Senate, joined a spokesperson for the statewide LGBT group Equality Maryland in expressing confidence that the committee would soon approve the bill.

“I just think you see politics going on,” said Madaleno, who is gay. “It’s a high-profile issue and you’ve got some legislators who are supporters of the bill who still say they are supporting the bill who are just trying to bring attention to issues that they care about as well.”

He added, “I remain optimistic that we’re going to have the votes needed to pass it when it gets to the floor. Obviously, the first step is getting it through the committee. And we have the majority of the committee who are co-sponsors.”

Linsey Pecikonis, communications manager for Equality Maryland, said her group also remains confident that the committee will approve the bill.

“None of the delegates that have been supporting the bill in the past – none of them have wavered in their support,” Pecikonis said. “They just want to make sure that they are drawing attention and people are aware of other issues that are going on within the committee.”

Madaleno noted that opponents of the bill would seize on the wrinkle that surfaced in the House Tuesday to advance their claim that support for the bill is eroding.

“I think that just speaks to what we have to do, and that is, do the same thing — pull out all the stops,” he said. “No one should take anyone for granted in this debate. People should be calling their delegates and asking them to vote for the bill.”