Long, perhaps best-known for his work representing Apple in the popular "Apple vs. PC" commercials, spoke at a rally in Richmond on Sunday. The "Gotta Vote" bus is rolling through multiple swing states ahead of looming voter registration deadlines. 

Monday is the last day new voters can register in key swing state Virginia.

Long, who originally signed up as @not_THAT_Jlo but was able to switch to @justinlong, tweeted that he was convinced to join Twitter "after years of being a proud twitter-less Luddite" by Shiloh Jolie-Pitt. He went on to tweet from the bus tour, where he is accompanying Virginia Democratic Party Chairman Brian Moran, former Michigan Gov. Jennifer Granholm and Rep. Jim MoranJames (Jim) Patrick MoranDems face close polls in must-win Virginia Billionaire Trump donor hires lobbyists to help vets Lawmakers: Chaffetz has a point on housing stipend MORE (D-Va.).

Long and the Gotta Vote tour were in Iowa on Monday.

The actor also played Mitt Romney in a parody video for progressive advocacy group earlier this year.