The hip-hop band are currently working on their next LP, which has a political thread, Adam "Ad-Rock" Horovitz told Billboard.
"We hope to have it out sometime next year. It's a lot of vocals, a lot of words - very wordy. And it's political, depending on what you call political. You know, if toilet talk and fart jokes are political, which they can be, in that sense yeah, very," he said.
Horovitz said they called a number of artists to join them for stages on the road, and those who agreed include Sheryl Crow, Ben Harper, Jack Johnson, Norah Jones, Crosby & Nash, Santogold and Tenacious D.
He said: "70 million people is a lot of people to not vote. So this all happened really quick, like a month or so ago and within the past few weeks, literally. We were just stressing on what to do and then we were like, 'We're a band and we play shows, so let's go to these swing states'. We thought it would be a good idea to get people to vote."
The 'Get Out And Vote' tour begins on October 27 and will run until November 2, two days before the presidential elections are scheduled to be held.