After multiple failed attempts to get statewide slot machines, Maryland voters approved a statewide referendum on election day to legalize 15,000 slot machines in five locations by 2011. The measure passed by roughly 59% to 41%, and was supported by Gov. Martin O'Malley and legislators. Backers said slot revenues could approach $1.2 billion annually and help make up an expected $1.7 billion shortfall in next year's state budget.