Hillary Rodham Clinton has chosen a veteran New York political operative who ran her husband's 1996 reelection effort in the state to oversee her Senate campaign, according to several sources.

Clinton has held off for weeks on naming a campaign manager, despite Democrats' mounting calls that she take more concrete steps toward an official Senate candidacy. The sources said, however, that she has settled on Bill de Blasio, who is on President Clinton's executive branch payroll as head of the New York office of the federal Department of Housing and Urban Development.

Asked about the choice of de Blasio, Clinton's spokesman for the exploratory campaign, Howard Wolfson, said, "We will have an announcement within the next month and beyond that I don't have a comment." De Blasio could not be reached for comment.

"Mrs. Clinton is lucky to have him," said one source close to de Blasio, who described him as close to both HUD Secretary Andrew M. Cuomo and his father, former New York governor Mario Cuomo. "He is the perfect person to run the campaign." De Blasio has also worked closely with Harold Ickes, a former Clinton White House deputy chief of staff who has been Mrs. Clinton's chief adviser in her Senate race.

It is unclear when de Blasio will take on the new post, the source said, adding, "The details are still being worked out with the campaign."

One source close to the campaign characterized the deal as "in its final stages," while two other Democrats familiar with the talks said the announcement was apparently delayed because de Blasio has been on vacation. One characterized the delay as a political mistake on the campaign's part, because announcing that the first lady had hired a campaign manager could have silenced critics within the Democratic Party who this week have urged her to get more serious about the race.

On Monday, the state party chairman, Judith Hope, joked with a reporter that perhaps Clinton should "give up her day job" as first lady to concentrate on the race. And with controversy still raging in New York about Clinton's visit last week to the West Bank, Democratic circles have been buzzing with speculation that she may not run after all.

De Blasio's name has circulated for weeks as the top prospect for the campaign manager's job. But campaign officials have been reluctant to discuss it on the record and have often been defensive on the question of whether campaign bumps and missteps were associated with the absence of a formal manager.

"When voters go into the voting booth next year, they won't be asking when we hired a campaign manager," Wolfson said.

Although Clinton does not yet have a manager for her campaign, it has turned out to be an unusually early-starting Senate contest. Her likely Republican opponent, New York City Mayor Rudolph Giuliani, has been running campaign ads in upstate New York for more than two weeks--the first by any Senate candidate in the country.

But in another move criticized by some Democrats, Clinton's campaign has not responded to those ads directly, instead allowing the state Democratic Party to spend "soft" money to bankroll television ads urging upstate voters to "call Hillary" and "support leadership that's on our side."