Cynthia Nixon ENGAGED To Christine Marinoni

Sunday Cynthia Nixon announced her engagement to longtime partner Christine Marinoni during an Action=Marriage Equality rally in midtown New York to fight for same-sex marriages.

Nixon was joined at the rally not by her fiancee, to whom she became engaged last month, but by her "Sex and the City" costar Kristin Davis, David Hyde Pierce and New York Governor David Paterson.

The pair have been dating since 2003.

Nixon has a son and a daughter from a previous relationship.

Below is a photo of Nixon as she shows of her new engagement ring during the rally, and below that Nixon's hand Friday night.

Thousands of people attended a rally on Avenue of the Americas near Times Square yesterday sponsored by Broadway Impact in support of marriage equality in New York. A short time before that, state Senator Ruben Diaz Sr. bussed in approximately 10,000 evangelical bigots for an anti-gay rally of his own on Third Avenue in front of the Governor's office.

“I think we would definitely [get married] if it became legal in New York,” Nixon told Access Hollywood. “I don’t really want to get married to get married pretend. I think we’d like to do it in a real, actual, legal way that the state would recognize.”

At the rally, which was held to draw support for same-sex unions in New York state, Nixon revealed she became engaged last month. The couple has been together since late 2003. Nixon and her Sex and the City compatriots -- Sarah Jessica Parker, Kim Cattrall, and Kristin Davis -- are set to begin filming the sequel to the big-screen smash later this summer.

Actors Cynthia Nixon and David Hyde Pierce, along with Governor Paterson and New York Mayor Michael Bloomberg showed their support Sunday in New York City. A bill to legalize gay marriage passed in the house last week and has now moved on to the senate.

"The legalization of same sex marriage in New York is overdue and we do have 35, four days to pass it this session and we really, we really want to do it," said Nixon.

"What we're talking about here is plain and simple, should the government be in the business of deciding who can marry whom and I don't think they should be," said Mayor Bloomberg.