Candidates Barnstorm Battleground States on Final Friday of 2016 Presidential Race

Trump and Clinton each campaigned in three separate states today.

On Friday, Trump campaigned in New Hampshire, Ohio and Pennsylvania. Clinton, meanwhile, held events in Pennsylvania, Ohio and Michigan, a traditionally blue state that the Trump campaign hopes to turn red this year. Clinton's visits to Michigan and Pennsylvania are a sign the Democrat is looking to protect her firewall of states she hopes will help put her over the 270 electoral vote threshold to win on Tuesday.

Speaking in Atkinson, New Hampshire, Trump waxed nostalgic about his win in February’s primary there, “You know this is where it all began New Hampshire. ...This was our first victory and I never forgot that.”

But Trump didn’t miss an opportunity to lash out at his opponent, even raising the specter of former President Bill Clinton’s impeachment while attacking Hillary Clinton’s email controversy.

“If she were to win, it would create an unprecedented constitutional crisis. What a mess,” Trump said. “We went through it with him with the impeachment and the lies. Aren't we tired of this stuff?”

Hillary Clinton held her first campaign event of the day at Heinz Field, the home of the Pittsburgh Steelers, urging the crowd, “If you know anybody here in Pittsburgh or in western Pennsylvania who’s thinking about voting for Trump, please stage an intervention before it’s too late."

ABC News rates New Hampshire and Pennsylvania as leaning Democratic and Ohio as leaning Republican. Tossup races include Arizona, Florida, North Carolina and Maine’s 2nd congressional district.

More than 34 million Americans have already cast their ballots, according to data from The Associated Press. Republicans appear to be making up ground in some key swing states, including Arizona, Colorado and Nevada, bouncing back to 2012 early voting levels after a slow start in some states, and surpassing past early voting levels in others.

ABC News' Gary Langer, Gregory Holyk, Chad Kiewiet De Jonge and Sofi Sinozich contributed reporting.