MONTPELIER, Vt. (AP) – Four years ago, Vermont was deeply divided over civil unions for same-sex couples.

Rural roads were dotted with “Take Back Vermont” signs posted by people angry at the state’s first-in-the-nation law granting most of the rights and responsibilities of marriage to same-sex couples.

An Associated Press exit poll in 2000 found respondents split 49 percent to 49 percent on whether civil unions were a good idea. Seventeen lawmakers who supported the law lost their seats, shifting control of the Vermont House to the Republicans.

New exit polling shows in a striking way that a strong majority of Vermonters has grown comfortable with – or at least accepting of – granting legal recognition to same-sex relationships.

This year’s exit poll asked respondents to choose between three options for legal recognition of same-sex relationships: full marriage, civil unions or no recognition. Forty percent said they support marriage, 37 percent civil unions and 21 percent neither.

The poll of 698 Vermont voters as they left 15 randomly selected polling places around the state was conducted for AP and television networks by Edison Media Research and Mitofsky International. Results were subject to sampling error of plus or minus 6 percentage points.

Supporters of marriage rights for same-sex couples say Vermont’s experience, coupled with the absence of a backlash on Election Day against Massachusetts lawmakers who supported same-sex marriage in that state, means that in the two American places where legal recognition has been extended to same-sex couples, public acceptance is growing.

“We’ve known all along that once people got past their fear of the unknown and the reality was known, the extension of full equality to same-sex couples would be seen as a good,” said Middlebury attorney Beth Robinson. She was one of the lawyers who brought the lawsuit that prompted the state Supreme Court to call on lawmakers to give marriage-like rights to same-sex couples.

“The sky hasn’t fallen in Vermont,” Robinson said. “A few families are more secure and nobody’s any worse off.”

Matt Daniels, head of the Washington-based group Alliance For Marriage, said he is not impressed with the change in Vermont, or with the absence of a backlash against Massachusetts lawmakers who supported same-sex marriage there.

“The clear, unmistakable, incontrovertible evidence of the national trend is exactly the polar opposite” of the growing acceptance in Massachusetts and Vermont, Daniels said. His comment came one day after 11 states voted for amendments to their constitutions that would ban same-sex marriage. Seven of the measures would ban civil unions as well.

AP exit polls found that nationally, 25 percent supported same-sex marriage, 35 percent supported civil unions and 37 percent said they opposed either.

When a Massachusetts court decision late last year put the issue before lawmakers there, opponents promised to oust lawmakers who supported same-sex marriage. The Massachusetts exit poll didn’t include a question about same-sex marriage. But every Bay State lawmaker who supported gay rights won another term in the Legislature.

Noting the lack in Massachusetts of the sort of backlash that occurred four years earlier in Vermont, an official with one group who advocates for same-sex marriage, said Vermont cleared the trail.

“I think Massachusetts really needs to thank Vermont,” said Marty Rouse, campaign director with Mass Equality. Rouse, who said he still considers Vermont home, worked as a party operative with Vermont Democrats in the 2000 campaigns to try to stem the anti-civil-union tide.

“I think Vermont helped to educate Massachusetts,” Rouse said. “Because of the geographical proximity of the two states, Massachusetts residents got to see that equal marriage rights for same-sex couples were not as frightening as some might have thought.”

Another sign that Vermont’s anti-civil-union fervor has died down: The Orleans County Republican Committee ran an ad the week before the election in the weekly Barton Chronicle naming seven candidates who had been endorsed by a group that advocates for same-sex marriage.

“Can we afford to elect representatives and senators who are committed to dividing Vermonters once again?” the ad asked. Three of the seven targeted candidates won, and a longtime Republican lawmaker who led the anti-civil-union effort in the 2000 legislative session lost.

Stephen Cable, head of the conservative group Vermont Renewal, said he did not believe the record for civil unions in Vermont had been as rosy as supporters claimed.

He pointed to a custody dispute between two women who dissolved their civil union. Lisa Miller-Jenkins had a child while in a civil union with Janet Miller-Jenkins.

Civil unions also have bolstered families, said Rep. Bill Lippert, D-Hinesburg. Lippert was the only openly gay Vermont lawmaker when civil unions were debated in 2000. He was one of at least five who won election this year.

“Vermont has a program to encourage gay and lesbian couples to adopt children,” Lippert said. “So now there are children who have families now [who] wouldn’t have otherwise.”

Lippert said Vermont’s 2000 law led a trend. “When we created civil unions, marriage for gay and lesbian couples did not exist anywhere in the world.” Now it exists in Belgium, the Netherlands, several Canadian provinces and Massachusetts and something similar exists in Vermont.

Eric Davis, a professor of political science at Middlebury College, said the growing acceptance of legal recognition for same-sex couples might be a case study in the evolution of a political idea.

It took decades from the late 19th century, when some states first gave women the right to vote, to the passage of the women’s suffrage amendment to the U.S. Constitution in 1920. History may be speeding up, as the writer Alvin Toffler predicted in the 1970 best seller Future Shock. Only 16 years elapsed from the time the issue of civil rights was first given a place on the Democrats’ national platform in 1948 to when civil rights legislation passed the Congress in 1964.

“Part of what’s going on is that Vermonters are moving past the controversy. Civil unions are now an accepted part of the fabric of the state,” Davis said. “It’s been a remarkable transformation in just five years.”