The New York League of Conservation Voters for the first time teamed up with Mayor Michael Bloomberg to raise money for a candidate for higher office, as the environmental group joined the mayor last night at a fund-raiser for state Sen. Mark Grisanti’s re-election campaign. Earlier this month the League launched a bipartisan initiative to elect green-friendly lawmakers, with the most resources going to back Grisanti and Assemblyman George Latimer, who’s also running for state Senate. Of course, the mayor has been a big backer of the four Republican state senators – including Grisanti – who were pivotal votes in the passage of same-sex marriage legislation last year. But the mayor also spoke about the importance of conservation yesterday and Grisanti echoed the mayor, saying conservation was one of his key issues as chair of the environmental conservation committee. Some 75 people showed up for the event at Bloomberg’s Upper East Side townhouse, with tickets going for a minimum of $1,000.