When it comes to Pennsylvania politics and personalities, many of those voters voiced deep disapproval of Corbett and concern over the direction in which the state is headed. Coloring their perspective: the governor's handling of the Sandusky investigation when he was state attorney general.
"There are a lot of things impacting his numbers, but the Penn State situation is a big factor," said Adam Geller, chief executive of the Republican polling firm National Research Inc., who conducted the poll with Jeffrey Plaut, founding partner of the Democratic polling firm Global Strategy Group.
"There is no question this is a raw wound for many voters," Geller said. "And it is not showing any signs of healing."
The telephone survey, conducted last Tuesday through Thursday, found that a majority of voters likely to participate in the fall election - 56 percent - believe the state is headed in the wrong direction. The pollsters put the margin of error at plus or minus 4 percentage points.
Voters gave Corbett low job performance ratings, with 38 percent approving and 52 percent disapproving, though they were more evenly split on whether they like him personally (40 percent gave him a favorable rating, 44 percent an unfavorable one).
That is a lower grade than those same Pennsylvania voters gave neighboring New Jersey Gov. Christie - 41 percent rated him favorably, while 28 percent did not.
Reacting Friday to the poll numbers, Corbett spokesman Kevin Harley noted that the governor is not on the ballot this year, and argued that his administration has worked hard over the last 18 months to reduce the size and cost of government and restore state finances wracked by deficits.
"Leadership is not a popularity contest," said Harley.
Accurate or not, voters' perceptions of Corbett's handling of the Sandusky investigation have taken a bite out of his popularity. Only 17 percent of those polled said they approved of how he dealt with the investigation when he was state attorney general.
For voter Paul Kuty, 54, of Newtown, Bucks County, Corbett's handling of Penn State looms large.
Kuty, a Democrat who did not vote for Corbett in 2010, said he believed that as attorney general Corbett had purposely slowed the Sandusky investigation because he was running for governor.
"He didn't want to be the bad guy," said Kuty, a senior tax analyst with the IRS. "So he waited for someone else to do the dirty work."
No credible evidence has surfaced that Corbett put the brakes on the case for political reasons. The governor has repeatedly defended his handling of the matter, explaining that child sexual abuse investigations take time and that he and his investigators worked to build an airtight case that would ensure Sandusky never again harmed a child.
And that, Corbett has pointed out, is what happened: Sandusky was convicted on 45 of 48 counts. "The facts of Penn State are, Tom Corbett investigated Jerry Sandusky when nobody else would," said Harley. "And the result of his investigation is that Jerry Sandusky will spend the rest of his life in prison."
Despite Corbett's explanations, questions have lingered in the public arena.
Whether that translates into trouble for Corbett if he runs for reelection in two years remains a question mark, said political analyst and pollster G. Terry Madonna.
Corbett's real problem, Madonna believes, comes down to dollars and cents - or the lack thereof.
Facing declining revenues and a lackluster economy, the governor has made steep cuts two years in a row in aid to education, and to a number of health and social-welfare programs.
Those cuts, Madonna said, have taken a bigger bite out of Corbett's approval ratings than anything else.
This spring and summer, Corbett began shaking up his inner circle and raising his public profile at the urging of political advisers and fund-raisers, who were worried he was beginning to suffer from an image problem, evidenced in sagging poll numbers and a chilly relationship with the GOP-controlled legislature.
Notwithstanding those changes, Madonna said, "It doesn't change the financial reality he is dealing with."
But Erick Mazzoni, 31, a Republican from Philadelphia, thinks Corbett has managed those finances just fine.
"What he's doing is not easy stuff," said Mazzoni, who works in commercial real estate. "You are going to upset people. But at end of the day it's the smart way to run things. I would vote for him again."
Other elected officials fared better in the poll.
For instance, if the election were held today, voters would handily return Casey to Washington. The Democratic senator with one of the best-known last names in Pennsylvania politics held a 19-point lead over his lesser-known challenger, Republican Tom Smith.
Plaut, the Democratic pollster, said a whopping 80 percent of the voters surveyed reported being familiar with the senator, compared with Smith's 31 percent. A solid chunk of voters like Casey, too. He received a 50 percent favorability rating to Smith's 19 percent.
"I think Casey is a case unto himself," said Plaut. "He exists beyond traditional or typical notions of party, and has a 19-point lead in a race that does not appear to be a target for the national committees. So, absent a seismic change in the environment, Casey looks to be strong."
Supporters of Smith, a western Pennsylvanian who grew up on a farm and built a successful coal business, beg to differ. Campaign spokeswoman Megan Piwowar said in an e-mail: "The poll is a snapshot in time and what it represents will change over time with our continued message running on the airwaves across the state. Our message will make clear that Sen. Bob Casey has failed to offer a single solution to get our economy growing, halt the skyrocketing debt, or even reduce the job-crushing regulations."
In the race for attorney general, Kane, the Democratic nominee, is leading Freed, the Republican, by 11 points. But with 31 percent of voters still undecided on that contest, the picture could change before Nov. 6.
"A third of the electorate doesn't even have an opinion yet," said Plaut. "The race is wide open."
Contact Angela Couloumbis at 717-787-5934 or firstname.lastname@example.org, or follow on Twitter @AngelasInk.