On the afternoon of November 23, 2009, the New Jersey Senate Democrats chose Sweeney as State Senate President over the incumbent, former governor Richard Codey. He took office on January 12, 2010. In the absence of the governor and lieutenant governor, Sweeney served as acting governor of New Jersey during the eastern seaboard storm of December 2010. In January 2010, Senate President-elect Sweeney abstained when the New Jersey Senate voted on the question of allowing same-sex couples to marry. Sweeney called his abstention a mistake and said that the issue was a civil rights issue, not a religious issue. In 2012, Senate President Sweeney was one of the prime sponsors of legislation that would legalize same-sex marriage for all New Jersey residents. The bill was approved in both houses of the Legislature, but ultimately vetoed by Governor Chris Christie, who instead favors putting the issue up for public referendum. In 2010, Senator Sweeney helped design and pass thirty bills, known collectively as "Back to Work NJ," that aimed to help create jobs and economic growth in New Jersey. In 2011, Sweeney proposed sweeping reforms to the public employee pension and health benefits systems that he estimates will save taxpayers over $120 billion over a 30-year period. Sweeney also helped craft the state's two-percent property tax cap in order to control rising property taxes. Senator Sweeney was named as a "Politician Who's Ahead of the Curve" by "Philadelphia Magazine" in 2011 for his continued support of shared services between local government units.