DENVER — A bill in the Colorado Legislature that would effectively do away with the Electoral College as we know it has passed the state Senate and moves to the state House of Representatives.

The bill - SB 42 - would tie Colorado's Electoral College votes to the outcome of the national popular vote once enough states adopt similar laws. Once 270 electoral votes-worth of states join the movement, the president will be chosen by whoever receives the most votes nationally, according to the nonprofit National Popular Vote.

This would be a massive shift from the way things are done now: Under the current electoral college rules, Colorado's nine votes go to the candidate in the state that gets the most votes, not the whole country.

Democratic Senator Mike Foote is a sponsor of the bill and said he thinks a change is needed.

"Every race, the statewide races, the legislative races - everything - is based on popular vote, and other states as well - the presidential is the only one that's not," Foote told 9NEWS.

The electoral college-versus-popular vote debate is not just semantics. For two recent elections - 2016 and 2000 - it would have changed who won the presidency.

The National Popular Vote Nonprofit is pushing for and tracking this legislation. So far 12 states have approved giving their electoral votes to the national popular vote winner for president. Some of the other states that have approved similar legislation include California, Illinois, New York and Washington state.

RELATED: Colorado state lawmakers float bill that would effectively do away with the electoral college

Should Colorado approve this, 13 states representing 181 electoral votes would be in. However, the "National Popular Vote Interstate Compact" can't take effect until enough states sign on to equal the 270 electoral votes needed to become president.

"The electoral college was designed for a certain reason, but it was also designed to have a lot of flexibility to go to the states," Foote said.

To read the full text of the bill in its current form, head here.

9NEWS political reporter Marshall Zelinger contributed to this report.

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