And in a theoretical head-to-head matchup in 2010 with Republican Danny Tarkanian of Las Vegas, Tarkanian got support from 45 percent of respondents compared with 40 percent for Reid. The poll has a margin of error of plus or minus 4 percentage points.

It's closer than a Mason-Dixon Polling & Research survey from mid-August that showed Reid trailing Tarkanian by 11 percentage points, but still suggests Reid has a tough row to hoe in order to serve another term. The Mason-Dixon poll was commissioned by the Review-Journal.

"Those are not good numbers for Reid," said Del Ali, president of Research 2000, which conducted the poll on behalf of the liberal Web site www.DailyKos.com.

"Tarkanian is really even with Reid in Clark (County), which is a disaster for any Democrat," Del Ali said.

Clark County is the most liberal part of the state.

Reid, who repeatedly criticized results of the Mason-Dixon poll because it surveyed just 400 people, didn't directly dispute results of the Research 2000 poll.

Through a spokesman, Reid emphasized his status as the highest-ranking Nevada politician and his efforts to help the state endure the recession.

"Every day, Senator Reid fights for Nevada families. He is working to help them stay in their homes, keep their jobs and access quality, affordable health care. Reid is a powerful voice for Nevada and will continue doing everything he can to help Nevadans weather the economic storm," Reid campaign manager Brandon Hall said via e-mail.

Tarkanian consultant Jamie Fisfis said the results reflect what he already knew: Early in the race, Tarkanian is running strong and Reid isn't.

"Here is another survey where Reid is struggling to stay above the 40 line, let alone the 50 line," Fisfis said.

If Reid's approval rating stays low, Fisfis says he expects attacks on challengers to increase in intensity.

"He is going to try and destroy whoever is the nominee. There is no other option," Fisfis said.

The poll had another potential Reid challenger, Nevada Republican party chairwoman Sue Lowden, in a dead heat with the incumbent, with Lowden getting support from 44 percent of respondents and Reid from 41 percent.

The Research 2000 poll also had some bad news for Sen. John Ensign, R-Nev., who is not up for re-election until 2012.

According to the survey, just 28 percent of respondents had a favorable view of Ensign, 53 percent had an unfavorable view and 19 percent had no opinion.

Ensign's political career has been in crisis since earlier this summer, when he confessed to an extramarital affair with an employee. The scandal gained momentum when it was revealed Ensign's family paid the family of the other woman $96,000.

Since then, Ensign has sidestepped questions about the affair and the payments at public stops in Lake Tahoe, Ely and Las Vegas.

Ensign's name, once among the most regarded in Nevada politics, has been reduced to the point that one Republican gubernatorial candidate, former North Las Vegas Mayor Mike Montandon, used it in an attack on federal judge Brian Sandoval, a potential rival for the Republican gubernatorial nomination.

Montandon's attack was based on a report that, in a meeting with several Republicans, Ensign claimed credit for recruiting Sandoval into the gubernatorial race.

"U.S. Sen. John Ensign displayed bad judgment when he had an affair with his best friend's wife, and now he's displaying more bad judgment in his endorsement and recruitment of Brian Sandoval for governor," Montandon said in a statement Wednesday.

Ensign hasn't responded to requests for comment on the Montandon slam or the latest poll results.

Still, despite the poll, the Montandon criticism, calls to resign from conservative radio talk show host Bill Manders of Reno and calls from a newspaper in Republican-heavy Ely for Ensign to meet with constituents in an uncontrolled setting, Ali says the junior senator's political career isn't as hopeless as it could be.

"If there was a shock, I'm surprised Ensign's unfavorables weren't higher, which I think is good news for him," Ali said.

There's still plenty of hope for Reid, too, Ali said. The Research 2000 poll showed 52 percent of respondents favored health reform that includes "a government-administered health insurance option that anyone can purchase to compete with private insurance plans," commonly referred to as a public option.

Support was especially strong among Democrats, of whom 80 percent approved, and independents, who approved at a rate of 50 percent.

Ali said it suggests Reid could use the issue to boost his status among those groups who could tilt the election in his favor.

"If there is a public option and it passes, and he has something to do with it, I don't see how that hurts him," Ali said.

Lowden consultant Robert Uithoven says he would welcome a campaign that comes down to a debate over health reform.

He says Republicans expect to alter how voters view the public option by emphasizing it could shift money from Medicare, a government-run health plan relied upon by senior citizens, and highlighting the potential cost to taxpayers.

"It is who can get out and effectively communicate exactly what this health care plan is," Uithoven said.

Contact reporter Benjamin Spillman at bspillman@reviewjournal.com or 702-477-3861.