Plenty of skeletons are rattling in the political closets of the Republican and Democratic presidential candidates this year.

A survey of 1,010 adults conducted by Scripps Howard News Service and Ohio University finds that many Americans voice concerns about candidates who have used cocaine, been married three times, have uncommon religious beliefs, have little government experience or are just plain too old.

The survey finds that almost every major candidate has a significant fault or political deficit that he or she must overcome.

"This is a very different field of candidates, a more wounded field than usual. That's going to make for a very interesting race," said Morgan Felchner, editor of Campaigns and Elections magazine.

One of the biggest obstacles facing Sen. John McCain, R-Ariz., is his age. He would be 72 when taking office. The survey found that 56 percent believe that most Americans will not accept such an elderly chief executive.

"That's kind of surprising," said historian Paul Boller Jr., who, at 90, has just published his latest history of the denizens of the White House titled "Presidential Diversions: Presidents at Play from George Washington to George W. Bush." "After all, people are living much longer these days. The public has got to get adjusted to this."

Adults in the survey were equally troubled over prospects of a president who tried cocaine, something that Sen. Barack Obama has admitted. Only 34 percent said they think most Americans would accept this, while 58 percent said it would not be acceptable.

The highest negative trait of all goes to candidates who have little government experience, a charge frequently leveled against Obama and former North Carolina Sen. John Edwards. Fifty-nine percent said they believe that most people would find lack of experience unacceptable.

Some candidates suffer from multiple challenges. Former New York Mayor Rudy Giuliani, who is the Republican front-runner in all national polls, has been married three times and would not abolish abortion rights, both unusual for a candidate seeking conservative voters. Less than half the adults in the survey thought that either would be acceptable to most people.

Democratic front-runner Hillary Clinton, the junior senator from New York, must overcome the political consequences of being the first competitive female presidential candidate in history and one who voted to authorize military actions in Iraq. Just slightly more than half thought that either being a woman or a former supporter of the war would be acceptable to most Americans.

"I honestly doubt that Americans are ready for a black president or a woman," Boller said.

The survey found that only 55 percent thought that a black president would be acceptable to most Americans.

Former Massachusetts Gov. Mitt Romney must persuade the Republican electorate, including many of the estimated 100 million evangelical Protestants, not to take offense at his Mormon faith. The poll found that 45 percent believe that a Mormon president would be unacceptable to most people.

The survey found that some personal traits do not seem to matter much. Most people believe that it's acceptable for a white presidential candidate to have adopted a black child (good news for McCain, who in 1991 adopted a dark-skinned orphan from Bangladesh) or to smoke tobacco (good news for Obama, although he's trying to quit.) The poll found that people are more accepting of candidates who tried marijuana when very young (also good news for Obama and, perhaps, other candidates.)

Few voice concern over a candidate who is very wealthy, which is good news for at least eight candidates who are millionaires, or who have lived the past 20 years in Washington, D.C.