[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2008/images/10/14/art.ayers.mccain.gi.jpg caption=" McCain plans to criticize Obama's ties to Ayers at Wednesday night's debate."]
(CNN) - John McCain and Sarah Palin appear to have dropped the subject of Barack Obama's connection to 1960's radical Bill Ayers from the campaign trail, but the Arizona senator said in an interview that aired Tuesday he'll likely bring it up at the third and final presidential debate Wednesday night.
The comments, during an interview with St. Louis radio station KMOX, come after Obama and Democratic VP candidate Joe Biden were sharply critical of McCain for targeting the Illinois senator over Ayers at campaign rallies, but not when the two last met for a presidential debate.
"I was astonished to hear him say that he was surprised I 'didn’t have the guts' to do that, because the fact is the question didn't come up in that fashion," McCain said of the last debate. "I think he's probably ensured it will come up this time."
McCain and Palin stepped up their criticism of Obama's past relationship with Ayers last week, as the GOP ticket's poll numbers continued to slide in the homestretch to Election Day. The campaign also released a string of ads that questioned Obama's truthfulness on the matter, in an effort to raise doubts about the Illinois senator's political origins and character. But the subject of Ayers was noticeably absent from both McCain and Palin's stump speeches Sunday and Monday, leading many political observers to conclude the campaign had deemed that line of attack ineffective.
Watch: Palin Renews Obama Attack
In the radio interview, McCain made clear he still thinks it's an issue.
"It’s not that I give a damn about some old washed up terrorist and his terrorist wife, who in 2001 said they wish they'd bombed more - what I care about, and what the American people care about, is whether he's being truthful," McCain told the St. Louis radio station.