Gay-marriage proponents celebrated another win in Maryland on Thursday after the state Senate approved a measure that would legalize same-sex unions. Gov. Martin O’Malley has vowed to sign the bill, which will make Maryland the eighth state to adopt gay marriage. Even though Maryland’s legislation has a large Democratic majority, there was still quite a bit of opposition. Factions of lawmakers with Catholic and evangelical ties tried to block the bill. The Maryland House of Delegates voted last week to approve gay marriage by a thin margin—71 to 67. Despite one of the largest Democratic majorities in any state legislature, backers of gay marriage in Maryland had to overcome fierce opposition from blocks of African-American lawmakers and those with strong Catholic and evangelical views to cobble together coalitions big enough to pass both chambers.