"Corporate donations, I think that is one of the biggest problems today," said Walter L. Cox Sr., 86, of Cleveland. "They are buying the White House. They are buying public office."
Cox, a Democrat, was one of many people in the poll who do not, in spite of the high court ruling, think corporate and union campaign spending should be unlimited.
The strong support for limiting the amount of money in politics stood alongside another poll finding that shows Americans have a robust view of the right to free speech. Seventy-one percent of the 1,006 adults in the AP-NCC poll said people should have the right to say what they please, even if their positions are deeply offensive to others.
The ringing endorsement of First Amendment freedoms matched the public's view of the Constitution as an enduring document, even as Americans hold the institutions of government, other than the military, in very low regard.
"The Constitution is 225 years old and 70 percent of Americans continue to believe that it's an enduring document that's relevant today, even as they lose faith in some of the people who have been given their job descriptions by the Constitution," said David Eisner, the constitution center's chief executive officer.
For the first time in the five years the poll has been conducted, more than 6 in 10 Americans favor giving same-sex couples the same government benefits as opposite-sex married couples. That's an issue, in one form or another, the Supreme Court could take up in the term that begins Oct. 1.
More than half of Americans support legal recognition of gay marriage, although that number is unchanged from a year ago. In the past three years, though, there has been both a significant uptick in support for gay marriage, from 46 percent to 53 percent, and a decline in opposition to it, from 53 percent to 42 percent.
Loretta Hamburg, 68, of Woodland Hills, Calif., tried to explain why support for gay marriage lags behind backing for same-sex benefits.
"If they've been in a long relationship and lived together and if it's a true relationship, long lasting, it would be OK to have the same rights," Hamburg said.
But she does not support a same-sex union because "it would open up a lot of other things, like a man wanting two or three wives. I believe in marriage. They could call it something else if they want to give it a different definition. But I don't think it's right and that's what I feel."
The poll also found a slight increase in the share of Americans who say voting rights for minorities require legal protection, although the public is divided over whether such laws still are needed. Sixty percent of Democrats say those protections are still needed, compared with 40 percent of independents and 33 percent of Republicans.
One potential influence was that the survey was conducted amid lawsuits and political rhetoric over the validity of voter identification laws in several states. The laws mainly have been backed by Republican lawmakers who say they want to combat voter fraud. Democrats, citing academic studies that found there is very little voter fraud, have called the laws thinly veiled attempts to make it harder for Democratic-leaning minority voters to cast ballots.
Two areas in which there has been little change in public attitudes in spite of major events are gun control and President Barack Obama's health care overhaul.
No matter that the Supreme Court upheld the health law, nearly three-fourths of Americans say the government should not have the power to require people to buy health insurance or pay a penalty. It didn't matter in the poll whether the penalty was described as a tax or a fine.
The July 20 mass shooting at a suburban Denver movie theater that killed 12 people and wounded 58 others did not move opinion on gun rights, where 49 percent oppose gun control measures and 43 percent said limits on gun ownership would not infringe on the constitutional right to bear arms.
Retired Army Col. Glenn Werther, 62, called the Colorado shootings a "horrible thing," but said gun control is not the answer to curbing violence. "There are crazy people out there. How you monitor that, I have no idea," said Werther, a resident of Broad Brook, Conn., and a member of the National Rifle Association. "People are going to get guns that should not have them."
The National Constitution Center is a nonpartisan, nonprofit organization that operates a Philadelphia museum and other educational programs about the Constitution.
The AP-NCC Poll was conducted by GfK Roper Public Affairs & Corporate Communications from Aug. 16-20, using landline and cellphone interviews with 1,006 randomly chosen adults. The margin of sampling error was plus or minus 3.9 percentage points.