Bob Schieffer in honky tonky heaven

Oh, to be in Nashville on Sunday.

CBS News' Bob Schieffer will be taking the stage at the Grand Ole Opry for the first time with his band, Honky Tonk Confidential. The Opry is hosting a special show Sunday evening in honor of the presidential debate to be held Tuesday at Nashville's Belmont U. That one will be moderated by NBC News' Tom Brokaw.

Schieffer gets his turn as a debate moderator on the third and final encounter between Barack Obama and John McCain on Oct. 15 at Hofstra U. in Hempstead, N.Y. On Sunday, Schieffer will be in good company on the Opry stage. He's landed the 8:10-8:15 p.m. slot, sandwiched between perfs by Tricia Yearwood and Brad Paisley.

Meanwhile, McCain and Obama will have their hands full trying to match the perf of their No. 2s last night. The Joe Biden-Sarah Palin debate drew a whopping 70 million viewers across the Big Four, CNN, MSNBC, CNBC, Fox News, BBC America and Telemundo. It also out-drew the first McCain-Obama match (52.4 million) by nearly 20 million.

The Biden-Palin aud included 35.7 million femmes and 30.4 million men of voting age, according to Nielsen. (Among the Big Three, ABC grabbed the most with 13.1 million, followed by 12.8 million on NBC and 11.1 million on CBS. Fox News registered its most-watched telecast ever with 11.1 million.)

The Biden-Palin bout easily out-rated the previous most-watched veep debate, Geraldine Ferraro-George Bush in 1984 (56.7 million), and the 2004 contest between John Edwards and Dick Cheney (43.6 million).