Money matters. That's what gay newspaper Chelsea Now reports:

The groups that backed same sex marriage outspent their opponents by roughly three-to-one during the fight to enact gay marriage in New York.

New Yorkers United for Marriage (NYUM), a coalition formed by the Empire State Pride Agenda (ESPA), New York’s statewide gay lobbying group, Freedom to Marry, the Human Rights Campaign (HRC), Marriage Equality New York, and the Log Cabin Republicans, spent $1.86 million on its marriage campaign in the first six months of 2011. That cash was spent on television ads, direct mail, and voter canvassing.

...Separately, some NYUM members, such as HRC, ESPA, and Freedom to Marry made additional expenditures on their own that collectively exceeded $1 million. Then a slew of other groups spent smaller amounts on lobbying. The Gill Action Fund, a political group founded by philanthropist Tim Gill, spent $80,000 on lobbying and the Gay Men’s Health Crisis (GMHC) spent a small amount. Altogether, marriage supporters spent at least $3 million in the first six months of 2011.

... Speaking at July 25 forum sponsored by the law firm Fried, Frank, Harris, Shriver & Jacobson, Brian Ellner, a senior strategist at HRC, said that in 2009 constituent calls to senators “ran 10, 20, 30 to one against…We knew from the get go that that had to be reversed.”

The coalition hired 35 fulltime canvassers who worked statewide and it produced 135,000 calls, letters or other contacts with legislators.