A Maryland House committee began debate on a gay marriage bill on Friday, one day after the Senate gave its approval.

The chamber's six openly gay members pleaded with the House Judiciary Committee to approve the bill.

“This debate is not about abstractions, this debate is not about definition, it's about the thousands of families who will be protected by this law,” said Delegate Heather Mizeur, a Democrat, as she motioned to her wife of two years, Deborah Mizeur.

The Senate approved the measure on Thursday with the assistance of one Republican, Senator Allan Kittleman, who joined 24 Democrats in voting for the bill.

A majority of members on the House committee support gay marriage and passage appears assured. However, supporters on Friday acknowledged they have yet to lock down a majority in the House, considered the more liberal chamber on social issues.

“We have about 69 of the 71 firm commitments that we need,” Mizeur told Baltimore's NBC affiliate WBAL. “And we have more than a handful of folks who are undecided but leaning our way that we think will be able to deliver in the coming days.”

Passage of out the committee could happen as early as Tuesday. And the full House could take a final vote on the measure by Friday.

Opponents, led by Delegate Don Dwyer, have mounted a campaign to derail the legislation.

“Homosexuality will be taught at some level to children attending public schools as has been ordered by the court in various states,” Dwyer said during a morning press conference on Friday.

The Maryland Republican Party has begun blanketing parts of the state with robocalls, which tell voters that Democrats are working to “destroy traditional marriage.”

“They are eroding the values [this] country and state were founded on by redefining marriage,” a female says in the message.

The National Organization for Marriage (NOM), the nation's most vociferous opponent of gay marriage, and the Family Research Council (FRC), have promised to mount a campaign to repeal the law, if approved by lawmakers.

Analysts believe opponents could easily put the question on next year's ballot. But supporters of marriage equality are hoping to make Maryland the first state to vote in their favor. Recent polls found a narrow majority (51%) of voters favor giving gay and lesbian couples the benefits of marriage.

Governor Martin O'Malley has pledged to sign the bill into law, which would make Maryland the sixth state to legalize the institution.