The Colorado House is taking up a bill this week that would change how the country elects the president — if enough other states get on board.

The bill, passed by the Senate 19-16 last month, would add Colorado to a growing list of states that have pledged to give their Electoral College votes to whomever wins the national popular vote for president. The House has scheduled its first hearing for Tuesday afternoon.

“We’re still counting votes,” said Rep. Jeni James Arndt, D-Fort Collins, one of the bill’s sponsors. “This isn’t a foregone conclusion.”

The idea of states making an end run around the Electoral College through their legislatures rather than attempting to amend the U.S. Constitution has been around for nearly two decades. Colorado Senate Democrats first passed it in 2006, but their counterparts in the House did not follow suit.

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It has been picking up support among Democrats nationwide since the 2016 election of President Donald Trump. Hillary Clinton received nearly 3 million more votes but lost the election in the Electoral College.

“If we had the popular vote now and were trying to switch it to our current system where some states had more say than others, people would be losing their minds,” Arndt said.

The compact of states that have agreed to the change so far hold 172 electoral votes of the 270 needed. Supporters expect more states to introduce national popular vote bills in 2019, although it’s not clear how many will pass — especially in the 30 statehouses where Republicans control both chambers.

Many Republicans’ position is that the Electoral College is a prescient design by the founders that puts large and small states on more equal footing and ultimately keeps them united.

“What national popular vote does is completely sidestep the idea of states electing the president,” said state Sen. Bob Gardner, R-Colorado Springs. “It was never intended that the president would be popularly elected.”

Another GOP concern is that less populous, rural areas that tend to vote Republican could be overwhelmed by major metropolitan areas that trend Democratic.

But Arndt isn’t convinced big population centers would get all the attention and influence in a national popular vote system. California represented 12 percent of the U.S. voting population in 2016, and Trump won about 32 percent of those votes without campaigning hard for the state.

Both small and large states that aren’t considered battlegrounds are routinely ignored by presidential candidates now.

“What if you woke up and realized that even as a Democrat in Indiana or a Republican in California your vote counted,” Arndt said. “You’d have this idea that we’re doing this together.”

The Constitution says each state gets one Electoral College vote for every member of Congress, but it doesn’t say how state legislatures can award those votes. That’s where supporters of the national popular vote movement see an opportunity. They believe that means it’s constitutional for state legislatures to give their delegates to whomever wins the national popular vote.

Gardner disagrees, arguing that fundamentally altering the system that way would require a constitutional amendment.

The bills in Colorado and elsewhere have been written to ensure the switch won’t go into effect until the compact has enough delegates to determine the outcome of the presidential election.

New Mexico, with its five votes, is debating whether to join the compact this year. Maryland was the first state to join in 2007. California joined in 2011, and New York passed it into law in 2014.

Democrats don’t control enough statehouses to surpass the 270-vote threshold without some Republican support, said Sen. Mike Foote, D-Lafayette, another sponsor of Colorado’s bill.

Sen. Paul Lundeen, R-Monument, said Democrats might be sorry if they’re successful, much in the way getting rid of a U.S. Senate rule that required 60 votes to confirm federal judges has come back to haunt them.

“This is one of those arguments around ‘shall we solve an immediate challenge and pressure point around a political impulse of today, or should we consider our posterity the way the founders did,'” Lundeen said.