Since the 18th century, the United States has used the Electoral College, made up of 538 individual electors, to elect its presidents instead of going by the popular vote.

The Electoral College has recently come under scrutiny after two presidents in the last 20 years won the Electoral College despite losing the national popular vote.

14 states and the District of Columbia have joined a movement to bypass the Electoral College and join the National Popular Vote Interstate Compact, in which member states pledge to give all their Electoral College votes to the winner of the popular vote.

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Since the 18th century, the United States has used the Electoral College, made up of 538 individual electors from 50 states and the District of Columbia who vote on behalf of their states instead of the national popular vote, to elect its presidents.

Every state except Maine and Nebraska uses a "winner take all" system that pledges all the state's Electoral College votes to the candidate that earns more than 50% of the vote. A presidential candidate needs a majority of 270 Electoral College votes to win.

In the past 20 years, the "winner take all" structure of the Electoral College has come under scrutiny after Presidents George W. Bush and Donald Trump were elected by the Electoral College despite losing the popular vote.

While supporters of the Electoral College, including 2020 presidential candidate Andrew Yang, say that it ensures smaller states get adequate representation and aren't ignored in national campaigns, its opponents argue the system has led to un-democratic outcomes.

Read more: You'll hear these 4 arguments in defense of the Electoral College — here's why they're wrong

Now, a growing number of Democratic presidential candidates have come out in favor of scrapping the institution.

A recent INSIDER poll found that 54% of Americans support electing the president by popular vote, with just 30% of respondents preferring the Electoral College.

Since a change to the constitution to get rid of the Electoral College is highly unlikely, some states are taking matters into their own hands to try and bypass the system.

Since 2007, 14 states and the District of Columbia have joined the National Popular Vote Interstate Compact, in which member states pledge to give all their Electoral College votes to the nationwide winner of the presidential popular vote — regardless of which candidate wins their own state.

The states already in the compact hold a total of 189 electoral votes, a little over a third of the total Electoral College. The compact will formally go into effect and hold legal weight once states that hold a combined total of 270 Electoral College votes between them join it.

Here are the states that are currently part of the compact: