A new poll found Monday that Sen. Robert Menendez (D-N.J.) faces low approval numbers going into his 2012 reelection effort.

Thirty-one percent of New Jersey's registered voters say they have a favorable opinion of Menendez, while 25 percent have an unfavorable opinion of the first-term Democrat.

A full 29 percent of the state's voters were unsure of their feelings toward Menendez, a new Fairleigh Dickinson/PublicMind poll found, and 15 percent of New Jersey voters said they hadn't heard of Menendez.

New Jersey is seen as a reliably Democratic state, and incumbents don't always have the highest approval numbers anyway. But Republicans are hoping a Senate electoral map in 2012 that tips in their favor will allow them to go on offense in the Garden State, where Republican Chris Christie won the governorship in 2009.

One sign of trouble might rest in Menendez's numbers with independents. Twenty-four percent of independent voters view him favorably, while 27 percent have an unfavorable opinion.

By comparison, New Jersey's veteran senator, Frank Lautenberg (D), has a 42-31 percent favorability rating among all registered voters.

The poll, conducted Nov. 15-21, has a 3.5 percent margin of error.