Colorado has joined a list of states that plan to allocate their electoral votes to whichever candidate wins the nationwide popular vote.

Gov. Jared Polis (D) signed the measure into law Friday, uniting Colorado with 11 other states and the District of Columbia in the National Popular Vote Interstate Compact, whose members pledge to use their electoral votes on whichever candidate wins the national popular vote.

The bill will only take effect, however, if the law is passed by states representing at least 270 electoral college votes, which is the amount needed to win the presidency. With the addition of Colorado, that number now sits at 181.

Other jurisdictions that have enacted the legislation include Rhode Island, Vermont, Hawaii, Connecticut, Maryland, Massachusetts, Washington, New Jersey, New York, Illinois, California and the District of Columbia. New Mexico, whose senate approved the legislation earlier this week, could be the next state to join.

Because Republican-controlled legislatures haven’t embraced the effort, changing the electoral college delegate procedures in enough states to reach the 270 combined electoral votes needed to become president could be difficult, Reed Hundt, chairman and co-founder of Making Every Vote Count, told The Washington Post last month. The remaining states where the initiative may pass are smaller and left-leaning, he said.

Under the Constitution, states have the power to determine how they award their electoral votes in national elections. Most states have winner-take-all laws, which award all of its electoral votes to the presidential candidate who receives the most votes within the state. Two states, Maine and Nebraska, split their electoral votes.

Because many states are dominated either by the Democratic or Republican party, the winner of a presidential election is a foregone conclusion in those states. Also because electoral votes are reflective of the representation within the U.S. House and Senate, some states have very large electoral college contingencies, while others are much smaller. As a result, a handful of “battleground” states are where candidates often focus their attention. Still, candidates prefer to win as many states as possible and the popular vote to establish a public mandate for their agendas.

Five of the nation’s 45 presidents have taken office without winning the national popular vote, including Donald Trump. Electoral college losses can be narrow: If Sen. John F. Kerry had 60,000 additional votes in Ohio in 2004, he would have won the election, even though President George W. Bush was 3 million votes ahead in the popular vote.

Because of changes in state demographics, elections are now fought in a tiny number of swing states, Hundt told The Post. In the 2012, 2016 and 2020 elections, nearly 40 states, with about 80 percent of the country’s population, were or will be ignored by both candidates, he said.

"This is a new American demographic, which shows that the electoral system of the 18th century doesn’t work anymore,” he said. “No one at the time the Constitution was written thought that 80 percent of the population would be irrelevant.”

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