The Senate was set to reject the nomination of John Tower to run the Pentagon, and the White House said President Bush would name a replacement candidate quickly.

Republican Leader Bob Dole agreed to a late-afternoon vote and withdrew a last-minute bid to give Tower an extraordinary six-month trial period as secretary of defense to prove he can abstain from alcohol.There was no doubt about the outcome as the Senate went through the motions of debating the nomination through the final few hours before the roll call.

"The bottom line in this place is how many votes do you have, how many votes can you change, can you change any?" Dole said. "And I think it is fairly clear despite this good faith effort that it is not going to change any votes."

With the prospect of defeat inevitable, White House press secretary Marlin Fitzwater said, "If necessary, we'll come up with a (new) candidate very rapidly."

Names most frequently mentioned in White House speculation as a replacement are Sen. John Warner, R-Va., the ranking GOP member of the Senate Armed Services Committee and a former secretary of the Navy; former Defense Secretary Donald Rumsfeld; former Rep. Jack Edwards, R-Ala.; and national security adviser Brent Scowcroft.

Scowcroft replied "No" when asked Thursday morning if he was in line for the Pentagon job.

The most recent Associated Press survey showed 52 Democrats and one Republican committed to vote against Tower or leaning strongly in that direction. It showed 41 Republicans and three Democrats declared for Tower or leaning his way.

Nevertheless, the White House said it wanted to see the nomination go all the way to a vote.

As the time grew near, Sen. John Breaux, D-La., who had previously been undecided, announced against Tower. "This is simply too important a job to entrust in the nuclear age to some one who may have a problem with alcohol," he said.

Tower, meanwhile, traveled with his three daughters to the Pentagon, where they had coffee together. Afterward, he went back to work reviewing various administration proposals.

Senate Majority Leader George Mitchell, D-Maine, looking beyond the likely defeat, sought to repair damage caused by the bitter struggle to relations between the Senate and President Bush.

"I know what's in my heart and in my mind," he told reporters. "I want to directly, clearly and unambiguously say that this doesn't represent an effort to be harmful to the president."

"I hope and believe we can work together on important matters," Mitchell said. "The tension of this issue will have no long-lasting effect on the relationship. I want to say from the bottom of my heart that I hope this will be the case."

Sen. Phil Gramm, R-Texas, insisted on ABC's "Good Morning America" Thursday that the battle for confirmation was not yet lost.

"I think it's an uphill battle, but I still think it's do-able. What that means is you've got to get somebody to change. Is that easy? No. Is it likely? No. But is it possible? I think it is."

The battle over the Tower nomination has produced so much bitterness and division in the Senate that Mitchell told his colleagues on Wednesday: "The only thing worse than having to go through this thing once is having to go through it twice."

The already slim chance Tower would be confirmed was dealt a crushing blow on Wednesday as a parade of previously undecided Democratic senators announced they would vote "no."

Only Democrat Lloyd Bentsen of Texas said he would vote "yes," joining just two other Democrats who have made that decision.

Sens. Charles Robb, D-Va., Joseph Lieberman, D-Conn., J. Bennett Johnston, D-La., Dale Bumpers, D-Ark., and Claiborne Pell, D-R.I., all said they would vote against Tower.

Johnston said his reading of the FBI report on Tower leaves him with the clear impression that Tower's personality changes when he drinks heavily, leading to "a recklessness in the social sense" entirely different from his behavior when sober.