How exactly do Americans elect their president?

When election time rolls around in Canada, the rules are pretty simple.

Canadians cast a ballot for their local MP, and whichever party elects the most MPs to the House of Commons forms government. The leader of that party becomes our prime minister.

The relative ease of that system might be prompting a bit of envy these days in the United States, where the process for electing a president is far from straightforward.

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Our southern neighbours do not vote directly for their leader, nor is the president automatically the head of the party that wins the most seats in the House of Representatives or the U.S. Senate.

Here’s a look at how things will actually work on Nov. 8, and beyond.

Electing an elector

At its core, the American system revolves around the electoral college, a group of 538 representatives, or “electors,”  who have already pledged their support to (in this case) either Donald Trump or Hillary Clinton.

To win the White House, you need 270 electors on your side.

But here’s where things get really tricky: Even if an elector pledged to Trump gets the most public votes and wins, that person’s presidential vote won’t necessarily go Republican. In most states, if the majority of electors chosen by the public are Democrats, then the whole state goes blue. If they are mostly Republicans, all the electors go red.

It’s winner takes all.

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The electoral college system means that the size of a state matters. States with larger populations and lots of electoral votes, like California, New York and Texas, are important ones to claim. A lot of states (big and small) are already a lock for either the Republicans or the Democrats.

But a handful of states, like Florida, Ohio and Pennsylvania, remain undecided. These are the ‘swing states.’ And either Trump or Clinton will need them to claim the presidency.

The system is admittedly far from perfect. On several occasions, as weird as it sounds, the presidential candidate who earns the majority of the popular vote has ended up losing the election. George W. Bush didn’t have a majority when he became president in 2000.

The Faithless

As if that weren’t enough, in rare instances members of the electoral college have been known to unilaterally change their votes. Traditionally, each state’s electors gather in the capital city of that state to confirm their vote in mid-December.

The people who pull a last-minute switch are known as faithless electors, and there have only been about 160 of them in American history. But the divisiveness and controversy that have characterized this particular campaign could lead to more than the usual number this time around.

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One Republican elector, Baoky Vu, said publicly last summer that he would withhold his vote for Trump, for instance — even if the Republican side was chosen by the people of Vu’s traditionally red state of Georgia.

This was unlikely to change the outcome of the election, especially as Vu said he would vote for a write-in candidate (someone whose name doesn’t actually appear on the ballot), not Clinton. He eventually resigned from the electoral college.

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About half of U.S. states have a law against electors switching their votes so they no longer line up with the will of the people. But the Washington Post recently noted that “the penalties are usually small, including fines, and aren’t enforced.”

Georgia is one of 21 states that have no law on the books at all, so Vu was well within his rights to refuse to support Trump.