(CNN) -- Washington is joining two other states that have passed ballot measures making same-sex marriage legal, CNN is projecting.
After nearly two days of counting, the voting broke down this way: 1,269,917 residents are in favor of it while 1,146,439 are not. By Friday, 75 percent of precincts were reporting results.
Voters in Maine and Maryland also approved similar measures on Tuesday.
In Maryland, 51.9 percent of voters passed same-sex marriage.
Maine could begin granting marriage licenses to couples as early as mid-December.
Recent national surveys have shown shifting attitudes toward same-sex marriage, with a majority of Americans now approving of marriages between two men or two women. A June CNN/ORC poll, for example, reflected such a shift in opinion in the U.S.
Election Day brought two additional gains for proponents of same-sex marriage: Wisconsin elected America's first openly lesbian senator, Democrat Tammy Baldwin, and President Obama became the first president to openly support same-sex marriage and get re-elected.
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