(CNN) Maine's lawmakers passed a bill that would give the state's electoral votes to the presidential candidate who won the national popular vote, taking a step toward becoming the 15th state to enact such a law.

The Maine Senate voted 19-16 Tuesday to join the National Popular Vote Interstate Compact, which would give all committed states' electoral votes to the winning popular vote candidate should the group accrue the 270 votes necessary for a majority.

California, Colorado, Connecticut Delaware , Hawaii, Illinois, Maryland, Massachusetts, New Jersey, New Mexico , New York, Rhode Island, Vermont, Washington state and the District of Columbia have all committed to the pact. The most recent addition, New Mexico, put the total at 189 electoral votes.

Maine is currently one of two states, along with Nebraska, that splits its electoral college votes instead of adhering to the winner-takes-all policy most states follow. Should the Maine House pass and Gov. Janet Mills sign the bill, Maine would contribute another four votes towards the 270. CNN has reached out to Mills on whether she intends to sign the bill.

Former Maine Gov. Paul LePage alleged earlier this year that if such a law were to pass, "white people will not have anything to say."

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