Lawmakers gave it preliminary approval last week before the Legislature recessed. They plan to resume deliberations March 29, but the amendment is subject to more debate and back room strategizing and its passage is uncertain.
"Until something passes, everything is in play," said state Rep. Paul Loscocco.
The debate over same-sex marriage was prompted when the state's highest court ruled that gays and lesbians have a constitutional right to marry. The decision cleared the way for the nation's first legally sanctioned same-sex marriages, starting May 17.
The Massachusetts ruling touched off a wave of same-sex marriages around the country. Thousands wed in San Francisco, and officials in New York State, Oregon and New Mexico followed suit. Opponents of same-sex marriage battled back in courts, and President Bush said he wanted a constitutional ban on the practice.
In Massachusetts, lawmakers tried unsuccessfully to reach a compromise in February on a proposed same-sex marriage ban and took a month off. They then spent another 10 hours last week before taking another break just shy of a final round of voting in this year's legislative session.
When they resume the constitutional convention later this month, the proposed amendment to ban same-sex marriage but allow civil unions could end up with a slew of revisions.
Indeed, all that has happened so far has been a prelude to the nitty gritty of the final stages of legislative maneuvering. Lawmakers hope to get the issue before voters on the November 2006 ballot, but the amendment must be approved by two consecutive Legislatures for that to happen.
Few Statehouse veterans were willing to place bets on the outcome of the amendment.
"I honestly don't know what's going to happen," said GOP House Leader Bradley Jones, whose small band of Republicans could prove pivotal.
They are one of a handful of ideological factions whose shifting alliances have frustrated the predictions of longtime political watchers.
The Legislature's liberal wing is hoping to kill the question outright. They see it as an end run around the Massachusetts Supreme Judicial Court ruling.
If efforts to kill the proposed amendment succeed, the court decision would stand unchallenged. But liberals who are keen to do just that make up a relatively small minority on Beacon Hill, complicating their chances of quashing the marriage question.
They tried during last week's session, persuading friendly lawmakers to hold their noses and vote for what they viewed as the least Draconian version of the amendment, with the idea of switching back to kill it on a required third vote in hopes of ending the debate for the year.
The strategy failed, but same-sex marriage backers aren't giving up.
"We're picking up support every day," said Rep. David Linsky, a Democrat. "If you had said a year ago the Legislature would approve civil unions with full benefits for same sex couples, people would have said you were crazy."
Conservatives aren't much happier about the compromise amendment, saying they want an amendment that defines marriage as between a man and a women, but without creating civil unions. They are particularly concerned about language that would guarantee all the legal rights of marriage to same-sex couples who enter into civil unions.
One solution? Split the compromise amendment into two questions, one defining marriage and a second creating civil unions.
Jones is pushing the idea, although he's not sure there is enough support.
"I would not want to prejudge the outcome in any way, shape or form," he said.
In the middle are moderate lawmakers who want to appear cautious when it comes to redefining marriage, but don't want to seem deaf to the pleas of gay couples. They could ultimately decide whether the compromise amendment is approved, rejected or tinkered with beyond recognition.
The state's high court first ruled in November that the state's ban on same-sex marriage was unconstitutional gave lawmakers 180 days to fix the problem.
"Whether and whom to marry, how to express sexual intimacy, and whether and how to establish a family — these are among the most basic of every individual's liberty and due process rights," the majority opinion said. "And central to personal freedom and security is the assurance that the laws will apply equally to persons in similar situations."
In February, after the state Senate asked for clarification, the court ruled that only full, equal marriage rights for gay couples — rather than civil unions — would be constitutional, erasing any doubts that the nation's first same-sex marriages could take place in the state beginning in mid-May.
"The history of our nation has demonstrated that separate is seldom, if ever, equal," the four justices who ruled in favor of same-sex marriage wrote in the advisory opinion. A bill that would allow for civil unions, but falls short of marriage, makes for "unconstitutional, inferior, and discriminatory status for same-sex couples."