(CNN) - A new poll suggests that only three in ten Nevada voters hold a favorable opinion of Senator John Ensign, although most don't want Ensign to resign in the wake of his confession of an extra marital affair with a former staffer. But when the poll, conducted by Mason-Dixon for the Las Vegas Journal Review, asked whether Ensign should run for re-election, less than half the respondents said they would like to see his name on the ballot again when his current term expires.
The poll indicates that 31 percent have an unfavorable opinion of Nevada's junior senator, down eight points from June survey taken immediately after Ensign's admission, and down 22 points from May.
Ensign announced on June 16 that he had had a nine-month extramarital affair with a woman who worked on his campaign staff. Ensign said the relationship ended last August. The woman's husband worked in Ensign's Senate office.
"The Mason-Dixon poll indicates that the circumstances surrounding the affair, rather than the affair itself, are what bother Nevada voters," says CNN Polling Director Keating Holland. "Only three in ten say that the fact that Ensign had an affair is a very serious matter. But twice as many feel that way when told that the affair was with his wife's best friend, and half feel the same when told that the woman in question was the wife of a top Senate aide."
"Nevadans also seem bothered by the disconnect between Ensign's behavior and the image he presented to the public before the affair was public knowledge," Holland adds. "The poll asked respondents to react to this statement: "Ensign had an affair although he is a member of the family values group Promise Keepers." Fifty-eight percent of Nevadans say that they view that very seriously."
Ensign has stated that he has no intention of resigning his seat and says he will run for re-election in 2012. Those plans are getting mixed reviews from his constituents.
Fifty four percent of those questioned say they don't think Ensign should resign - still a majority but down from 62 percent last month. But running again is another matter. Forty-five percent say that Ensign should seek re-election; 43 percent say he should not.
"That's not good news for Ensign," Holland says. "An incumbent is usually considered to be in trouble if a question on re-election doesn't get support from at least 50 percent of his constituents. It looks like a lot of Nevada voters are OK with the idea of Ensign finishing out his term as long as he calls it quits after that."
Ensign's faced mounting pressure following revelations earlier this month that parents paid the family of his former mistress close to $100,000 after she was no longer working for the senator. A lawyer for Ensign said the payments were legally made as "gifts, accepted as gifts and complied with tax rules governing gifts."
The Mason Dixon/Las Vegas Journal Review poll was conducted July 14-15, with 400 Nevada voters questioned by telephone. The survey sampling error is plus or minus five percentage points.