Boston ? With gays and lesbians now legally wed in Massachusetts, foes of gay marriage vowed Tuesday to campaign hard, in state and national elections, for candidates willing to reverse the tide.

“It’s very difficult, once a right has been claimed in law, to reverse that right, but we’re going to try,” said the Rev. Christopher Coyne, spokesman for the Roman Catholic Archdiocese of Boston.

The election battle will be waged on two main fronts — an effort nationally to elect congressional candidates supporting a constitutional ban on gay marriage, and an effort in Massachusetts to tilt the balance in the Legislature by ousting 10 to 20 lawmakers who opposed a state ban.

“We’re not going to let this issue go away,” said Kristian Mineau, president of the conservative Massachusetts Family Institute. “Our theme is ‘Remember in November.”‘

More than 1,000 same-sex couples — including scores from other states — have obtained marriage licenses since Massachusetts on Monday became the first state to allow gays to wed.

Protests were few, and sparsely attended, but Mineau said that reflected a deliberate decision by his group and others to avoid confrontations and to focus their energy against politicians, not gay couples.

“Homosexual couples are not the enemy,” said Raymond Flynn, a former Boston mayor and foe of gay marriage. “The enemy is the legislators who ignored and betrayed the people of Massachusetts by not giving them an opportunity to express their point of view.”

Coyne said Catholic Church leaders, though avoiding partisan politics, would make clear to Catholic voters that gay marriage is a factor they should consider when casting their votes this fall.

However, he acknowledged that the task of gay-marriage opponents was now more daunting.

“Obviously the issue has become so much more complex now with the reality of same-sex marriage,” he said. “When you talk about withdrawing that reality from these couples, you’re just opening a whole can of worms.”

Nationally, conservative leaders are working to build support for a proposed federal constitutional amendment — pending in Congress — that would prohibit gay marriages nationwide.

Tony Perkins, president of the Washington-based Family Research Council, said the amendment was the only sure defense against the expected wave of lawsuits by same-sex couples who marry in Massachusetts, then return home to other states and seek recognition of their unions there.

“This issue is boiling,” Perkins said. “It’s gone from an academic debate to a real public policy crisis.”

The federal amendment must first be supported by two-thirds of both the House and Senate, then be ratified by at least 38 legislatures, representing three-quarters of the states.