It appears stories about U.S. Senator Bob Menendez being involved with underage prostitutes in the Dominican Republic have been sufficiently debunked, but news reports about him possibly improperly helping a big-time donor friend are hurting his poll numbers.

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Today's Quinnipiac University survey shows Menendez' job approval rating has bounced back to 40 - 37 percent from a negative 36 - 41 percent approval rating in a February poll.

The negative rating, in the wake of allegations of impropriety, marked a 15-point drop from a 51 - 33 percent approval in January.

"The fall-out from those scandal stories has wounded Sen. Robert Menendez, but it looks like he has stopped the bleeding and even recovered a little," says poll director Mickey Carroll. "A substantial number of voters say the attacks are 'just politics,' but a majority thinks the allegations should be investigated."

New Jersey voters are divided 35 - 36 percent, with 29 percent undecided, on whether Menendez is honest and trustworthy. Last month, voters said 44 - 28 percent that he is not honest and trustworthy.

Garden Staters say 40 - 35 percent, with 25 percent undecided, that they are satisfied with the way Menendez is handling this matter. The controversy is worth investigation, 53 percent of voters say, while 30 percent say it is politically motivated.

From March 19 - 24, Quinnipiac University surveyed 1,129 registered voters with a margin of error of +/- 2.9 percentage points. Live interviewers call land lines and cell phones.