With his home state set to begin marrying same-sex couples on Monday, Sen. John F. Kerry (D-Mass.) reiterated his opposition to the idea yesterday, even as he met with gay and lesbian groups to shore up their support.

The presumptive Democratic nominee has long opposed gay marriage, favoring instead state-sanctioned civil unions that extend legal protections to gay couples.

Yet Kerry has taken several positions on the issue: He voted against the 1996 Defense of Marriage Act, which defined marriage as a union only of a man and woman, saying it amounted to gay-bashing. Kerry has opposed President Bush's call for a constitutional amendment to ban same-sex marriage but said in February that he favors such a ban in Massachusetts.

"If the Massachusetts legislature crafts an appropriate amendment that provides for partnership and civil unions, then I would support it, and it would advance the goal of equal protection," he told the Boston Globe.

Kerry's careful line is likely to come under increasing scrutiny as Massachusetts becomes the first state to sanction gay marriages, under a ruling by the state's Supreme Judicial Court. Massachusetts's capital, Boston, is also the site of the 2004 Democratic National Convention in late July.

Kerry's apparent discomfort with the issue showed at a news conference yesterday at his campaign headquarters in Washington. Asked by a reporter what he would say "on a personal level" to same-sex couples married in his state, Kerry said: "It's not my job to start parceling advice on something personal like that. I personally believe marriage is between a man and a woman, and in extending our rights under the Constitution in a nondiscriminatory manner."

Asked if he would offer his congratulations to the newly married, Kerry replied: "I obviously wish everyone happiness. I want everyone to feel fulfilled and happy in their lives. The way to do that is by respecting every citizen's rights under the Constitution."

Republicans are likely to tie worldwide publicity over the state's action to Kerry in an effort to paint him as a northeastern liberal who is out of touch with the values of the rest of the country. Polls show a majority of Americans, including many Democrats, opposed to granting full marital status to same-sex couples. Yesterday, Bush campaign officials said Kerry's statements reinforce their portrait of him as inconsistent on major issues. "This represents his typical pattern of confusing and contradictory statements," said Bush campaign spokesman Steve Schmidt.

Gay and lesbian groups, however, said they enthusiastically support Kerry after meeting with him yesterday. "His commitment to equality and fairness to all Americans, including gay and lesbian Americans, is real," said one participant, Winnie Stachelberg, political director of the Human Rights Campaign, the nation's largest gay rights group. "He knows when politics are being played and when the president is trying to jump-start the election on the backs of gay people. Rewriting the Constitution is wrong, and it's discrimination, pure and simple."

Kerry yesterday picked up the endorsement of the 12,000-member International Brotherhood of Police Officers, a group that had supported Bush in 2000.

Kerry also met with D.C. Mayor Anthony A. Williams (D), Del. Eleanor Holmes Norton (D-D.C.) and D.C. Democratic Party Chairman A. Scott Bolden, and he said he will fight for voting representation in Congress and greater federal aid for the nation's capital if he is elected president.

The 30-minute meeting came a day after black members of Congress from battleground states pressed Kerry's campaign to do more to win support from black voters.

Staff writer Spencer S. Hsu contributed to this report.

Sen. John F. Kerry shakes hands with Jerry Flynn, whose group, the International Brotherhood of Police Officers, endorsed him for president.Del. Eleanor Holmes Norton emerges from a meeting with Kerry. The candidate said he will fight for D.C. voting representation in Congress if he is elected president.