The good news for Arizona Sen. John McCain, the likely Republican presidential nominee, is that most Americans don't think he's too old to be president.
The bad news is that most Americans don't realize how old he is.
In a USA TODAY/Gallup Poll taken Thursday through Sunday, nearly six in 10 underestimated his age, which is 71. More than a third lopped off six years or more when asked to name their "best guess."
And Democratic presidential candidate Barack Obama?
By an even bigger margin, Americans said he's not too young to be president. Still, about four in 10 overestimated his age, which is 46, while half underestimated it.
For New York Sen. Hillary Rodham Clinton, two-thirds of Americans pegged her as younger than her age of 60.
If McCain and Obama are the nominees, the generational divide between them — McCain was 24 years old and a Navy aviator when Obama was born — will be unmistakable. Obama has mentioned McCain's long service to the nation in a way that the Republican's strategists see as deliberately valedictory.
"It's nice that he thinks so much of John McCain and 'his half-century of service,' " Rick Davis, McCain's campaign manager, says. "I don't mind engaging on what that half-century of service has been."
McCain's experience is a significant advantage for him, at least at the moment: 70% of those surveyed say he has the experience necessary to be a good president; 46% say that of Obama.
Obama has an edge among those seeking a new direction for the country. Of those surveyed, 42% called "leadership skills and vision" as most important in determining their vote; 22% cited experience.
In the abstract, Americans have reservations about electing a president in his 70s.
Last March, a USA TODAY survey found that four in 10 Americans said they wouldn't vote for a 72-year-old who was nominated by their party and otherwise qualified for the presidency.
In the new survey, older Americans — those 55 and older — were most likely to express concerns that McCain was too old and Obama too young.
If elected, McCain would be the oldest person to assume the presidency. (Ronald Reagan was 70 when he took office in 1981.) Obama would be the fifth-youngest president — after Theodore Roosevelt, John Kennedy, Bill Clinton and Ulysses Grant.
Obama could ease concerns about his age by displaying knowledge and wisdom in campaign debates. McCain could help put to rest concerns about his age by showing vigor on the campaign trail.
Democrats shouldn't count on tapping unease about McCain's age, cautions William Galston of the Brookings Institution.
He was an aide to Walter Mondale in 1984, when Reagan's riposte in the second campaign debate — "I am not going to exploit for political purposes my opponent's youth and inexperience" — turned the issue to his advantage.
"I've seen this movie before, and it didn't come out right the first time," Galston says. "Voters are going to have to judge for themselves whether someone is either too old or too young to be president."