Sen. Edward Kennedy on Monday questioned what he said were Samuel Alito's multiple explanations for not immediately disqualifying himself from a case involving the Vanguard companies, which handle his mutual fund investments.

Kennedy, D-Mass., said in a letter to the Supreme Court nominee: "You have given at least six different answers to the basic question of why you not only sat on the case, but presided, signed orders and joined an opinion upholding Vanguard's position in that case."

Kennedy will be one of 18 senators to question Alito at his Judiciary Committee confirmation hearings Jan. 9, and made clear that the Vanguard issue will come up.

White House spokesman Stephen Schmidt said: "It is increasingly clear that there is no answer that Judge Alito can give on this question that will satisfy senators like Chuck Schumer and Sen. Kennedy, who are making it increasingly clear that they intend to give no consideration to the nomination of Sam Alito and that they will vote against him the same way they voted against (now Chief Judge John) Roberts."

Alito pledged in 1990 that he would recuse himself from cases involving the Vanguard companies. Alito's liberal opponents say his participation in a 2002 Vanguard case raises doubts about the judge's fitness for the Supreme Court.

Getting more information about the Vanguard case now would be "in the interest of a smoother and less confrontational confirmation process," Kennedy said.

Alito sat on a three-judge panel that ruled unanimously in favor of Vanguard on a case involving the account of a deceased investor. The investor's widow sought a new review and Alito's disqualification, citing his substantial investments.

Alito and his supporters have repeatedly said he did nothing wrong. After the complaint, Alito wrote the chief judge of the 3rd Circuit that he did not believe he was required to disqualify himself but he would voluntarily step aside.

Alito and his supporters have also offered other explanations, Kennedy said, including that there was a computer failure or glitch that let the case slip through; that his promise to senators was for his "initial service;" and that his mutual fund holdings were not an issue.

Alito holds six-figure investments with Vanguard.

Kennedy sent Alito questions about each of the answers that he and his supporters have given for his participation in the Vanguard case. "I urge you to provide prompt and clear written answers to the many remaining questions about your failure to recuse yourself," he said.