Associated Press

SPRINGFIELD, Ill. — Illinois Senate Democrats delayed a floor vote Thursday on legislation to make the state the 10th in the nation to legalize gay marriage, but the sponsor expressed confidence there would be enough votes to pass it soon.

Sen. Heather Steans said two supportive Democrats and a Republican were missing from the General Assembly’s lame-duck session, forcing her to pull back from pressing the issue that had momentum from the November elections and public encouragement from President Barack Obama.

But Steans, a Chicago Democrat, said the delay would only push a vote into next week or, at the latest, soon after the new Legislature is sworn in Jan. 9.

“This is definitely a question of when, not if,” Steans said. “This is the right thing to be doing.”

Democrats hold a 35-24 majority in the Senate, but not every member is on board with extending marriage rights to same-sex couples.

The issue’s backers pressed the matter in the waning days of the 97th General Assembly to take advantage of soaring support in the state and nationally. Even though Democrats will claim a 40-19 advantage in the new session, newcomers will bring more diverse views.

The plan, which would remove from state law a prohibition on marriage between two people of the same sex, comes just 18 months after Illinois recognized civil unions. It is riding a wave from November ballot questions in several states bolstering gay marriage and support from Obama, whose political career began in the Illinois Senate.

But it has faced a bumpy ride this week, which began with high expectations. Steans’ attempt to amend marriage language onto an existing bill Wednesday night stalled when Republicans demanded a roll call on a procedural measure and defeated the bill’s progress.

A new vehicle for the legislation was still scheduled for a vote before the influential Senate Executive Committee Thursday, but that meeting had been delayed for hours as Democrats scrambled to gather enough votes.

One Democrat was out of the country and another had a family issue to attend, while a GOP supporter couldn’t attend because of a death in the family.