NEW YORK (Reuters) - New Jersey's Democrat-controlled state legislature will vote next week on bills to legalize same-sex marriage, the Democratic leadership said on Monday, adding pressure to Governor Chris Christie who opposes the measure.

The state senate has scheduled a vote on February 13 and the assembly will take up the issue three days later. A similar bid to approve marriage for same-sex couples was defeated by the senate two years ago.

Christie, a Republican party star who decided against entering the 2012 presidential race despite a high-profile courtship from top Republican donors, has repeatedly said he would veto a gay marriage bill if it were to come to his desk.

It was not clear that the legislation would win the support of two-thirds of both houses -- the threshold for overriding a governor's veto.

New Jersey has allowed civil unions between gay couples since 2007. A recent Quinnipiac University poll found New Jersey voters support gay marriage by a margin of 52 to 42 percent.

More than 40 states ban or refuse to recognize gay marriage, but six states, as well as the District of Columbia, allow it. Gay marriage is legal in New York, Massachusetts, Connecticut, Vermont, New Hampshire and Iowa.

A bill to legalize same-sex marriage in Washington state won state senate approval earlier this month, and gay rights activists in Maine say they plan to bring the issue to voters in a referendum.

(Reporting By Edith Honan; Editing by Cynthia Johnston)