From TPM:

The McCain campaign and the Republican National Committee are pumping a robocall into multiple states that directly alleges that Obama has "worked closely" with "domestic terrorist Bill Ayers," whose organization has "killed Americans," according to multiple reader reports and an audio recording we listened to.The caller begins by announcing that he's calling on behalf of McCain and the RNC. the call continues:

"You need to know that Barack Obama has worked closely with domestic terrorist Bill Ayers, whose organization bombed the U.S. Capitol, the Pentagon, a judge's home, and killed Americans. And Democrats will enact an extreme leftist agenda if they take control of Washington. Barack Obama and his democratic allies lack the judgment to lead our country."

The call concludes by saying it was "paid for by McCain-Palin 2008 and the Republican National Committee."