(CNN) - John McCain has learned his lesson: Don't ever cancel on David Letterman.
Appearing on the late night comedian's show Thursday, the Republican presidential candidate apologized for skipping out on a scheduled visit late last month that Letterman later made the subject of an ongoing joke.
"I screwed up," McCain told Letterman more than once in the interview that's set to air Thursday night.
McCain's appearance on the show comes three weeks to the day after after he raised the ire of the generally mild-mannered host by canceling at the last minute, citing his decision to suspend his presidential campaign because of the financial crisis.
"This doesn't smell right," Letterman said then, during a routine that only half appeared to be a joke. "This is not the way a tested hero behaves. Somebody's putting something in his Metamucil."
Letterman also didn't appear to buy the Arizona senator's explanation for the cancellation then, showing the audience a live feed of McCain preparing for an interview with CBS anchor Katie Couric. After praising McCain's record as a prisoner of war in Vietnam, he said, "This is not the John McCain I know, by God."
Letterman has repeatedly harped on McCain for the missed appearance, noting the Arizona senator's poll numbers appeared to begin to slide right after he skipped out on the show.
"Look at all the conversation I gave you. Including having Mr. Olbermann on," McCain told Letterman Thursday night, referencing the MSNBC liberal talk show host who filled in for him that night.
But Thursday's interview was not all fun and games, as Letterman pressed McCain on Republican VP Sarah Palin's preparedness to lead the country through "the next 9/11 attack.."
"Absolutely" she is, McCain said. "She has inspired Americans. That's the thing we need."
(CNN) - Republican vice presidential nominee Sarah Palin plans to appear on Saturday Night Live this weekend, multiple sources told CNN Thursday.
Saturday Night Live has featured opening skits in which former cast member and Palin lookalike Tina Fey portrays the Alaska governor. It was not known whether Fey also will appear on Saturday night's program.
The program airs at 11:30 p.m. ET.
The Statement: During an October 15 presidential debate at Hofstra University in Hempstead, New York, Republican presidential nominee Sen. John McCain attacked Democratic opponent Sen. Barack Obama for his stance on abortion. "Sen. Obama, as a member of the Illinois State Senate, voted in the Judiciary Committee against a law that would provide immediate medical attention to a child born of a failed abortion," McCain said.
Get the facts!
(CNN) – In the wake of an Associated Press report that the FBI is reviewing the results of several state inquiries into the conduct of ACORN, Sen. John McCain’s campaign called Thursday for Sen. Barack Obama to release additional information about the relationship between the embattled community organizing group and the Obama campaign.
“Barack Obama’s campaign must fully disclose the nature of his association with ACORN,” McCain campaign manager Rick Davis said in a statement Thursday.
The Obama campaign took issue with the McCain campaign's request. "ACORN never performed any voter registration work for the Obama campaign and Senator McCain’s campaign knows this," the Obama campaign said in an e-mail to CNN. "The real question is why they continue to assert something that isn’t true, and why they believe that attacking a group that Senator McCain himself praised as 'what makes America special' helps their campaign."
Related: 'We don't need ACORN's help,' says Obama
CNN has been unable to confirm a report by the Associated Press that the FBI is investigating whether ACORN helped foster voter registration fraud across the country as the presidential election approaches. Instead, several government sources have told CNN that the FBI and the Justice Department are reviewing documents provided by state investigations into ACORN to determine whether there is a basis to open a federal criminal investigation.
These developments at the federal level come nearly a week after six Republicans in the House of Representatives sent a letter to Attorney General Michael Mukasey requesting a federal investigation into ACORN’s voter registration activities. All of the House members who signed the letter to Mukasey had previously administered elections as Secretaries of States.
In a statement Thursday, ACORN said that it has not been contacted by any federal law enforcement agencies. "Should any investigation be forthcoming, we are confident that we would be exonerated," the group said. "We have always, and will continue to, work with any inquiry."
Watch: ACORN counters fraud charges
WASHINGTON (CNN) - Republicans launched an enormous wave of phone calls Thursday blasting Barack Obama for "having worked closely with domestic terrorist Bill Ayers," party sources said.
The calls are part of a $70 million last Republican push to get out the vote for John McCain on November 4, using calls, mailings and door-knocking in battleground states.
"Hundreds of thousands" of calls are being made in at least half a dozen hard-fought states including Virginia, North Carolina and Ohio, the sources said.
Some are recorded "robocalls," while others are live to comply with relevant state laws. The calls are being paid for jointly by the Republican party and the McCain campaign, according to a script provided by the Republican party.
The "robocalls" criticize Obama national security, his opposition to an Illinois measure that called for doctors to provide medical care to babies who survive botched abortions, his connection with former '60s radical William Ayers and his response to the financial crisis.
An Obama spokesman said the "dishonorable, dishonest" calls were a desperate move.
"John McCain's campaign has admitted that the economy is a losing issue for them, so he's chosen to launch dishonorable and dishonest attacks like this," Obama national spokesman Bill Burton said.
The calls come a day after McCain and Obama accused each other of running negative campaigns.
Republicans have been hammering Obama for weeks for his association with Ayers, a key figure in the Weather Underground of the Vietnam War era. The radical group took credit for a number of bombings, including of the Pentagon. A case against Ayers was thrown out of court because of misconduct by investigators. He is now an education professor in Chicago and has served on a board with Obama.
McCain said he did not care about "an old washed-up terrorist" like Ayers Wednesday night at his debate with Obama.
Obama condemned Ayers' actions of 40 years ago, and said the former radical was not involved in his campaign and would not advise him as president.
(Script of the call after the jump)
ELON, North Carolina (CNN) – Thursday marked the first day of early voting in North Carolina, a state unaccustomed to being in the political spotlight this late in a presidential election year.
But at an afternoon rally at Elon University near Greensboro, Republican Sarah Palin did not offer her supporters even the gentlest reminder that early voting - an opportunity both parties are working to take advantage of - is now underway at nearly 400 sites across the battleground state. Long lines at one-stop voting locations have been reported throughout North Carolina.
She did, however, mention the 85 degree heat.
“Thank you all for that very, very warm welcome to beautiful North Carolina, and it is warm,” she said. “Man, this Alaskan gal is … I’m roasting. This feels really good.”
In remarks for a campaign event at Downington, Pennsylvania, on Oct. 16, Republican presidential nominee Sen. John McCain said, "If I'm elected President, I won't fine ... families with children, as Senator Obama proposes, to force them into a new huge government-run health care program, while I keep the cost of the fine a secret until I hit you with it."
Get the facts!
New state polls show McCain continues to slide in key battleground states. (Getty Images)
(CNN) - John McCain continues to lose ground in three battleground states, new CNN polls of polls out Thursday suggest.
According to the new surveys, McCain is still slipping in Pennsylvania, Florida, and even Colorado - a state that hasn't voted for a Democratic presidential candidate since 1992.
In the new Pennsylvania poll of polls, McCain now trails Barack Obama by a 13 point margin, 53-40 percent. That deficit is up from 12 points in a poll of polls released earlier this week.
In Florida, the state that handily voted for President Bush in 2004, McCain trails Obama by 4 points in the latest CNN poll of polls, 49-45 percent. That's up from a 3 point gap there over the weekend.
And in Colorado, a longtime Republican stronghold where McCain has held the advantage for months, the new CNN poll of polls shows Obama on top by 6 percentage points, 50-44 percent. Earlier this week, Obama held a 5-point lead over McCain.
HEMPSTEAD, New York (CNN) –- Barack Obama is on track to spend more than $110 million on campaign commercials in October, an outstanding sum that does not include payment for the 30-minute network prime-time ads scheduled to air six days before Election Day.
Obama’s decision to opt out of the presidential public financing system has given him a distinct advantage over John McCain when it comes to airing political commercials. Obama’s daily spending on campaign ads is three times more than McCain’s – $4.5 million to $1.5 million – according to an analysis by TNSMI-Campaign Media Analysis Group, CNN’s consultant on political advertising.
Obama’s spending translates into about 7,700 airings of campaign commercials each day, more than double the 3,600 ads being run by McCain. Both candidates are running the ads in key battleground states. Obama is also on the air nationally, on network and cable, buying ads on NFL football games, soap operas and in primetime.
Obama is expected to spend between $1 million and $1.5 million on the 30-minute campaign commercials that will air on CBS, FOX and NBC on October 29, projects Evan Tracey, CMAG’s chief operating officer.
“This is more than just a message imbalance,” Tracey said. “This is, in media terms, a rout. John McCain is in a shouting match against a guy with a megaphone.”
Tracey estimates that by the end of the week, Obama will have spent more than President Bush did on campaign ads in 2004. During his successful re-election bid, Bush spent around $190 million - and the president went on the air in 2004 four months before Obama turned his focus to the general election in June of this year. To be fair, Obama has been running ads since June 2007 - during a primary battle that lasted far longer than anyone expected - but those commercials focused on his battle for the Democratic presidential nomination.
Sen. John McCain, speaking at the October 15 presidential debate in Hempstead, New York, said Sen. Joe Biden, the Democratic vice-presidential candidate, "had this cockamamie idea about dividing Iraq into three countries."