New York ? After the initial surge of elation and outrage, supporters and opponents of gay marriage are looking past a historic Massachusetts court ruling toward a nationwide, state-by-state struggle that will be complicated, nasty and politically treacherous.

Some gay couples are considering traveling to Massachusetts to get married, now that the state’s Supreme Judicial Court has ruled they should have that right within six months. Others hope for a ripple effect, triggered by lawsuits, that eventually will require their home states to recognize same-sex marriages.

“There are a lot of questions — couples are asking about blood tests, application forms,” said Corri Planck of the Family Pride Coalition, an advocacy group for gay families. “As a community, we haven’t had to pursue something like this before; it’s incredibly exciting.”

In the other camp, conservatives are urging Massachusetts lawmakers to somehow circumvent the court order and exhorting Congress to approve a constitutional amendment that would bar gay marriage nationwide.

“Most Americans don’t pay attention to this issue until it’s thrust upon them,” said Matt Daniels, whose Alliance for Marriage has promoted the amendment. “Now you’re going to see millions of them raising their voices. … They don’t believe gays and lesbians have the right to define marriage for everyone else.”

Energized by the court ruling, conservatives are railing against “judicial tyranny” and vow to make gay marriage a pivotal issue in the 2004 elections. William Donohue, president of the Catholic League, said the ruling could pave the way for polygamy; Nebraska Atty. Gen. Jon Bruning wondered aloud if a man could now marry his pet.

“We will fight courthouse to courthouse,” said Alan Sears, president of the Alliance Defense Fund, a conservative legal group

Determination is just as firm on the other side.

“We’ve gone to great lengths to put our family together; it was a lot of work and a lot of pain,” said Ken Manford of Dallas, who — along with his partner — has adopted a 2-year-old Guatemalan boy.

Manford said he and Jeffrey Roach, partners for 13 years, are considering going to Massachusetts to get married, but only if convinced it will have practical benefits.

Jeffrey Roach, left, and partner Ken Manford, right, with their 2-year-old adopted son Jackson Manford-Roach, middle, stand in front of their home in Dallas. Manford and Roach, partners for 13 years, are considering going to Massachusetts to get married next year.