The Senate race in New Jersey, which a Republican hasn't won in 34 years, remains virtually tied with less than two months before Election Day, a poll released Wednesday shows.

Among likely voters, including those leaning toward a candidate, Republican challenger Tom Kean Jr. holds a 48-45 percent edge over Democratic Sen. Robert Menendez, the Quinnipiac University poll showed. Six percent remain undecided. This survey of 688 likely voters has an error margin of plus or minus 3.5 percentage points.

Among the 1,233 registered voters surveyed, Menendez has a 41-38 percent edge. This survey has an error margin of plus or minus 3 percentage points.

The state's large bloc of unaffiliated voters is evenly split on whether they support Menendez or Kean, and they hold the key to deciding the election, said Clay Richards, assistant director of the Quinnipiac University Polling Institute. In recent history, these voters have swung Democratic.

"Just as importantly, 37 percent (of unaffiliated voters) say they could change their mind before Election Day," Richards said.

The poll held good and bad news for both candidates. By a 48-25 percent margin, voters agree with Menendez that Kean is a "George Bush Republican" who would support administration policies. Kean recently has been critical of Bush on various issues, including the war in Iraq, and has called for Defense Secretary Donald H. Rumsfeld to resign. New Jerseyans disapprove 64-33 percent of the way Bush is handling his job, the poll showed.

For Menendez, voters were asked about ethical concerns Kean has raised regarding a stock issue and the renting of a house to a nonprofit agency Menendez helped obtain federal funds. Menendez has never been charged with any wrongdoing during his 32 years in political office.

"More than four in 10 voters say they don't know if Menendez — or Kean, for that matter — can be described as honest or trustworthy," Richards said.

When asked what the main issue was for supporting either candidate, 52 percent of voters said it was their stand on issues. Kean and Menendez share many views: they favor abortion rights, embryonic stem cell research and are pro-environment. Menendez voted against sending troops to Iraq, while Kean has said he initially supported it, but adds now that significant mistakes have been made.

And for Kean, the son of former Gov. Thomas Kean, who chaired the Sept. 11 commission, 18 percent of voters said that was the reason they favored him.

Menendez was appointed to the Senate in January by Gov. Jon Corzine to serve out the remaining year of his term.