The Empire State Pride Agenda is encouraging the queer community to stop giving financial support to Hillary Clinton’s re-election campaign because of her opposition to same-sex marriage.

In a memorandum to board members, Alan Van Capelle, the executive director of the group, the Empire State Pride Agenda, said Mrs. Clinton was “a complete disappointment,” taking issue with her opposition to same-sex marriage and her support for the Defense of Marriage Act.

Mrs. Clinton supports civil unions between members of the same sex but opposes gay marriage. She also opposes a proposed consitutional amendment to ban same-sex marriage.

In his memo, which was reported on Tuesday on the Politicker Web site of The New York Observer, Mr. Van Capelle said that he refused to “lend my name and sell tickets” to any fund-raiser sponsored by a gay group for Mrs. Clinton’s re-election campaign. He said supporting such fund-raisers for Mrs. Clinton would “actually hurt” the gay and lesbian community.

“It will send a message to other elected officials that you can be working against us during this critical time and not suffer a negative pushback from the gay community,” he said. “We have become a community that throws money at politicians, and we demand nothing in return. And that’s what we get: nothing. It’s the wrong message to send.”

Clinton’s advisers respond: But gay people are coming to our party next month. Isn’t that enough?

Mrs. Clinton’s advisers countered that her support within the gay community runs deep, noting that a fund-raising event planned for next month will have prominent gay politicians and activists as hosts, including Christine C. Quinn, the New York City Council speaker, and Ethan Geto, a well-known lobbyist.