McCain came to his running mate's defense when asked on "GMA" about comments by former Secretary of State Lawrence Eagleburger, a McCain supporter, who criticized Palin's qualifications for vice president.
"Give her some time in office and I think she will be adequate," Eagleburger told National Public Radio. "I can't say she will be a genius in the job."
"Larry has never had a chance to meet Sarah," McCain told "GMA." "She has more experience than Sen. Obama and Sen. Biden put together."
Palin has been a favorite of the party's conservative base, however, leading to speculation about tension between McCain and Palin camps as the duo trail in the polls during the final grueling days of the campaign.
Earlier this week, Palin predicted victory during an interview with ABC News' "20/20."
"If it doesn't happen, Elizabeth Vargas asked her about the future," "GMA" anchor Robin Roberts said to McCain. "And she said she's not doing this for naught. Gov. Palin is not doing this for naught. Do you think she is the face of the Republican Party going forward?"
"I think to a large degree as vice president or, o r..." McCain said with a chuckle, trailing off before concluding, "She's united our country to a large degree. And she's in many ways an inspirational figure."
Watch Elizabeth Vargas Interview Sarah Palin Friday on "20/20" at 10 p.m. E.T
McCain also said Palin's background as governor of a small state was not a drawback.
"I would remind you, there was an obscure governor of a small state called Arkansas that everybody said wasn't qualified," he said, referring to former President Bill Clinton. "I didn't vote for him, but he got elected and re-elected."
McCain began his Halloween campaigning in Ohio, which he has made a must-win state for his White House ambitions.
The Arizona senator will be flanked by prominent Republicans at several points over four rallies in the Buckeye State as the campaign heads into its final weekend. Former New York City Mayor Rudy Giuliani and California Gov. Arnold Schwarzenegger will be on the trail to support McCain.
The candidate will also make an appearance this weekend on "Saturday Night Live," which has become an essential stop for candidates.
Two top Republicans the public won't see this weekend: President Bush and Vice President Dick Cheney. Bush remains in Washington as Sens. Barack Obama and John McCain fight to become his successor, and Cheney will be in Wyoming.
McCain released a new ad today featuring praise from an unlikely source -- Obama.
The ad, which will be shown in key battleground states, shows Obama praising McCain for his stand on climate change and that Obama often believes McCain is right.
Both McCain and Obama have been flooding the airwaves in the final lap of the 2008 presidential race, and a study by the Wisconsin Ad Project shows that McCain is being outspent by Obama by nearly three to one.
The Wisconsin Ad Project said that $38 million was spent on TV ads by both candidates and outside groups during a seven day period from Oct. 21 to Oct. 28. Most of that money, $21 million, was spent by Obama, the project said.
Those figures do not include the estimated $4 million Obama spent on his 30 minute infomercial earlier this week.
In addition, Obama is launching new ads in traditionally Republican strongholds, including McCain's home state of Arizona, as well as in North Dakota and Georgia.