Rep. Robert E. Andrews, a South Jersey Democrat, alleged yesterday that Hillary Rodham Clinton's campaign had deliberately tried to exploit tensions between Jews and blacks in her unsuccessful effort to gain the party's presidential nomination.

Andrews, a party superdelegate who had endorsed Clinton, said yesterday that he had brought up the issue this week because he believed talking about it would help reunite divided Democrats.

His allegation came just days after he lost a bruising primary battle to unseat the party's incumbent senior senator from New Jersey, Frank Lautenberg.

Andrews said he had received a call from a high-ranking person in Clinton's campaign shortly after he made some positive comments about Clinton's rival, Barack Obama, just before Pennsylvania's April 22 primary.

The caller told him about a campaign strategy to win Jewish voters by exploiting tensions between Jews and blacks, said Andrews, who declined to name the person who had called him.

"Frankly, I had a private conversation with a high-ranking person in the campaign . . . that used a racial line of argument that I found very disconcerting," he said. "It was extremely disconcerting given the rank of this person. It was very disturbing."

Andrews first discussed his allegations in an interview with the Star-Ledger of Newark that was published yesterday.

Clinton spokesman Phil Singer denied the allegation.

"Comments like these, coming so soon after Congressman Andrews' crushing defeat, are sad and divisive," Singer said.

Andrews said he had not divulged the call before this week because he did not want to appear to be making an unfair play for Obama supporters in his own primary campaign.

"I guess I'm a believer that you should talk honestly about problems before you can solve them," Andrews said.

He said he expected to switch his support from Clinton to Obama after the New York senator formally conceded the race, a move expected today.