One of these 3 men will be in charge of Canada by the end of the night - here's what happens next
The 11-week campaign has seen a tight three-way race between the incumbent Conservative Party under Stephen Harper, the Liberal Party under Justin Trudeau, and the New Democratic Party, or NDP, under Thomas Mulcair.
On Monday, we will find out who wins.
Harper and his Conservative party have been in power since early 2006. They've had a majority government since 2011.
For the first time in a long time, it looks like there could be a change.
If there is, it could have a big impact on everything from the Canadian dollar to the country's trade policies - and on Canada's decision whether to build the Keystone Pipeline.
Mostly, it will mean a lot of uncertainty ahead.
That's because whichever party wins will likely only win a minority government, and will have a harder time getting things done than with a majority government.
"Current polling suggests there are very high odds (~80%) of a minority outcome, indicating that policy uncertainty could persist," wrote Macquarie's David Doyle in an October 8, 2015, note.
If there is a minority government, one that wins but falls short of 170 seats, it will most likely be a lot more left-leaning than Harper's majority government has been. Beyond that, it's hard to say what will happen.
Here's where the three leading parties stack up on a number of major issues, per Doyle's note: