If Kean, a state legislator and son of former Gov. Thomas Kean, wins in November, he would be the first Republican to represent the state in the Senate in more than 20 years. The race is also a critical one as the Democrats struggle to take control of the Senate.
The Public Mind Poll, sponsored by Fairleigh Dickinson Public University, found that 36 percent of those surveyed said they would vote for Kean if the election were held now, compared to 25 percent for Menendez. But 37 percent were undecided.
Menendez, the son of Cuban immigrants, rose through the Democratic ranks to become the first Hispanic to represent a northeastern state in Congress and in the Senate. Jon Corzine, who takes office as governor Tuesday, named him to fill out the balance of his unexpired Senate term.
The poll found that Kean has more name recognition than Menendez. But voters said they did not know much about either man.