NEW YORK — Republicans endorsed an uncompromising position against gay unions Wednesday in a manifesto that contrasts with Vice President Dick Cheney's supportive comments about gay rights and the moderate face the party will show at next week's national convention.

A panel made up largely of conservative delegates approved platform language that calls for a constitutional amendment banning same-sex marriage and opposes legal recognition of any sort for gay civil unions.

The GOP's full platform committee, seeking to appease party members who support gay or abortion rights without embracing their positions, adopted language later that states Republicans "respect and accept" dissenting views.

"We are the party of the open door," said Mississippi Gov. Haley Barbour, who led platform deliberations on social issues.

But activists who support gay and abortion rights said they felt shut out and sharply criticized their party for adopting a hard line in advance of a convention next week that will seek support from swing voters and more liberal Republicans.

Christopher Barron of Log Cabin Republicans, a GOP gay-rights group, was livid after the panel endorsed the first-ever call for a constitutional gay-marriage ban in a GOP platform and went beyond that to oppose legal recognition of any same-sex unions.

"You can't craft a vicious, mean-spirited platform and then try to put lipstick on the pig by putting Rudy Giuliani and Arnold Schwarzenegger on in prime time," he said in an interview.

Giuliani, former New York mayor, and California Gov. Schwarzenegger are among moderate Republicans accorded prominent convention speaking slots.

Gary Bauer, who has campaigned for the marriage amendment and against abortion rights as president of the group American Values, said the platform draft solidifies the GOP as the "party of hearth and home."

The draft urges a constitutional ban on abortion, echoing a call from previous platforms, and endorses President Bush's restrictions on federal financing of stem cell research. Some Republicans want the restrictions loosened.

Andrea Lafferty of the Traditional Values Coalition advised the network of conservative churches not to worry about the religious right's exclusion from prime time next week, given the advances against gay rights.

"Don't be distracted by Schwarzenegger or Giuliani or even the vice president," she said. "It is what George Bush says that counts, and he has been faithful and fearless on this important issue."

She dismissed the other side as "RINOs" — Republicans in Name Only.

Each side claims to represent the voters Bush needs most for re-election, setting up a balancing act as the party tries to keep its religious conservatives satisfied and motivated without driving other voters away.