The running mates only get one chance to go head to head and it happens tonight in Farmville, Virginia.
FOX's Rachel Sutherland is there with more:
Farmville is home to Longwood University, which is hosting the 2016 Vice Presidential debate, just hours from now.
Republican Mike Pence and Democrat Tim Kaine will be debating each other, but they'll also likely defend their running mates, and attack the other party's presidential candidate tonight. Campaigning in Virginia today, Pence sounded like he's ready to defend Donald Trump:
(Pence) "Willing to fight for what he believes in and he's gonna fight for the American people all the way to the White House."
Kaine gets the first question of the 90-minute debate, which starts at 9 pm Eastern.
At Longwood University in Farmville, Virginia, Rachel Sutherland, FOX News.