The Minnesota House will hold a final floor vote Thursday on a measure to legalize same-sex marriage, after weeks of behind-the-scenes lobbying at the Capitol.

“I feel confident that we have the votes,” House Speaker Paul Thissen, DFL-Minneapolis, said Tuesday. “I personally want this to pass, but I also think it’s the right direction for Minnesota and where the future is headed.”

Thissen and many other legislators say they believe this legislation, if it passes, will be considered a turning point in the state’s history.

Advocates on both sides continue pressing legislators on what has become one of the most divisive issues of the session. Residents in districts where legislators remain undecided on the marriage issue are still being bombarded with automated phone calls from both sides urging them to contact their lawmaker.

Meanwhile, gay and lesbian advocates are embracing a last-minute change to the same-sex marriage proposal that would add the word “civil” in front of marriage in state law. The move is designed to clarify that the proposal will only change the legal definition marriage, not encroach of religious freedom for those who are opposed. The change is also designed to persuade a few Republicans to support same-sex marriage in Legislature and give the proposal a stronger bipartisan coalition.

Freshman Republican Rep, David FitzSimmons, R – Albertville, has offered the change. FitzSimmons could not be reached for comment. It is not clear whether the change will prompt him to vote for the measure.

“Minnesotans United supports this amendment, and we will encourage the members of the Minnesota House of Representatives to support it as well,” said Richard Carlbom, campaign manager for Minnesotans United, the lead group pushing for same-sex marriage. “Representative FitzSimmons’ amendment affirms the fact that Minnesotans want same-sex couples to have the freedom to marry in our state while also ensuring that clergy members and religious institutions are free to practice their beliefs free from government intrusion.”

So far not a single Republican House member has indicated their support for same-sex marriage.

But in recent days, opponents of same-sex marriage have sounded increasingly resigned to the notion there is little they can do to block the effort, as Democrats control the Legislature and the governor’s office.

“Elections have consequences, and the voters elected the entire team from the left wing of the DFL,” said state Rep. Michael Beard, R-Shakopee. “They can do pretty much anything they want to do, and that’s what’s going on.”

“I am saddened,” said Rep. Greg Davids, R-Preston. “I believe very strongly that marriage is simply between one man and one woman.”

Same-sex marriage advocates rejoiced after House leaders announced the vote, a signal that the measure is almost guaranteed to pass.

“Thursday’s vote in the Minnesota House of Representatives will be a historic victory for thousands of same-sex couples and families in our state,” said Richard Carlbom, campaign manager for Minnesotans United for All Families, which advocates same-sex marriage.

The proposal would go to the Senate for a final vote Monday after House passage. DFL Gov. Mark Dayton said he would sign the measure, making Minnesota the 12th state to legalize same-sex marriage.

If approved, gay and lesbian couples in Minnesota could get married starting Aug. 1.