NEW YORK (AP) – John McCain appeared on CBS’ “Late Show with David Letterman” Thursday night, telling the host “I screwed up” by canceling an earlier appearance on the show.

McCain offered his mea culpa shortly after sitting down onstage and being playfully asked by Letterman, “Can you stay?”

Letterman has kept up a relentless comic assault on McCain ever since the GOP presidential candidate canceled his Sept. 24 “Late Show” appearance to deal with the economy. He said he felt like an “ugly date,” and chose persistent McCain critic Keith Olbermann of MSNBC to fill in for McCain that night.

On Thursday, McCain appeared determined to show up for this guest appearance on the program: He flew by helicopter from Philadelphia to New York after a weather delay grounded his campaign plane.