DES MOINES, FEB. 6 -- Sen. Robert J. Dole (R-Kan.) is positioned to strike a damaging blow to Vice President Bush in the same Iowa Republican precinct caucuses that propelled Bush into national prominence eight years ago.

Dole, running as a fellow midwesterner who is "one of us," maintained a 37 percent to 23 percent lead over Bush in the Des Moines Register's Iowa Poll released today. And Rich Bond, Bush's deputy campaign manager, said only "a miracle upset" could save the vice president from defeat.

Bush forces have long tried to play down the importance of a Bush loss in the Iowa caucuses, the first major step in the presidential nominating process. But Bush has made a major commitment of resources here, and the increasingly acrimonious Iowa battle has exposed serious weaknesses in his candidacy that will follow him as he moves into more friendly territory in New Hampshire and the South in coming weeks.

The poll showed former television evangelist Pat Robertson, the big wild card in the race, in third place with the support of 13 percent of likely caucus-goers. Some experts predict Robertson could finish second Monday night if Dole and Bush fail to turn out their voters.

Robertson, who has built a base of support among evangelical Christians, is even more optimistic. "Ladies and gentlemen, I am going to win Iowa," he said at a rally Friday night.

He was followed closely in the poll of 660 likely GOP caucus-goers by Rep. Jack Kemp of New York, with 11 percent; former Delaware governor Pierre S. (Pete) du Pont IV with 7 percent and former secretary of state Alexander M. Haig Jr. with one percent in a race recently dominated by bitter exchanges between Bush and Dole.

The exchanges climaxed Thursday when an angry Dole demanded an apology from Bush on the floor of the U.S. Senate for a news release issued by Bush's Iowa campaign manager, George Wittgraf, that raised questions about a no-bid government contract awarded a former Dole aide.

The release accused Dole of "a record of cronyism" and a "history of mean-spiritedness" that "nearly single-handedly brought the Republican national ticket down to defeat" in 1976.

Although the vice president spent Friday and Saturday trying to avoid further squabbling, the Bush campaign helped keep the dispute alive into the weekend by documenting Dole's campaign attacks on Bush. Campaign manager Lee Atwater Friday sent a letter to Dole with 11 pages of examples of "the type of negative campaign which you have been engaged it." Bond accused Dole of "turning into Captain Queeg on the Senate floor."

Campaigning in Norwalk, Iowa, today, Dole complained, "There are a lot of personal things floating around here that aren't true."

Ignoring advice from his strategists, the senator then went on the offensive against Bush, charging that the Iran-contra scandal is a "cloud" over Bush's head that the Democrats are sure to exploit.

Dole became testy when questioned about his role in securing a government contract for John Palmer, a former aide, under a minority business program. "If you {can't} see a difference between writing a letter for a young black businessman in my state, trying to get him qualified, and the Iran-contra thing, then I've been asleep for a while," Dole said.

It was a sour note on which to end an Iowa campaign that has been more over resume and personality than issues from the start.

Dole has run as a familar neighbor, who understands agriculture and the problems of small-town Iowa because he grew up in a modest home in tiny Russell, Kan., and has proven he "can carry the ball" as the Republican leader of the Senate. He contrasts this with Bush's privileged background as the son of a U.S. senator and investment banker, and his role "standing on the sidelines" as vice president.

"People relate to Bob Dole here," said Iowa Dole chairman Steve Roberts. "There is a real midwestern-eastern thing. Midwesterners have an inferiority- superiority complex and don't relate easily to easterners."

Bush leaders concede that the Iran-contra scandal, the state's long-depressed farm economy and President Reagan's lack of popularity here have been "disadvantageous" for the vice president in Iowa, where 37 GOP national convention delegates are at stake. "This is an anti-Reagan, anti-defense, anti-contra aid state," Bond said.

On the final rush of vitriol, Wittgraf said he wrote the news release Tuesday night because he felt "Bob Dole has gotten largely a free ride in Iowa" and he thought two characteristics -- Dole's "mean-spiritness" and "history of cronyism" -- should be discussed.

Wittgraf said the exchange could "change the dynamic of the race."

It is unclear exactly how. Iowa has a history of squeaky-clean politics, and negative campaigning is frowned on here by many. Polls repeatedly have found that Iowans value integrity and honesty above all else in their politicians.

"As far as I'm concerned it is an act of desperation," said Dole state chairman Roberts. "I still can't understand why they started this. It seems like a great deal to risk for a small gain."

An Iowa victory is critical to Dole's hopes for the Republican nomination. The Kansas senator has campaigned here regularly since he finished eighth in the 1980 Iowa caucuses, and he has the full support here of popular Sen. Charles E. Grassley (R-Iowa) and his political organization.

Bush forces argue that they anticipated an Iowa loss here all along and can recover from a setback here. "If we don't win here we'll win in New Hampshire and be back in the saddle as the front-runner," said deputy campaign manager Bond. "If we pull off a miracle upset here, the Bob Dole candidacy is finished."

Bush, then a little-known former Texas congressman who had held a string of other government and political posts, won the 1980 caucuses, upsetting Ronald Reagan. Early last year, he was considered the front-runner here, largely by virtue of the strength of the political organization he had maintained here for eight years.

But Bush was badly embarrassed by a third-place finish behind Robertson and Dole in a straw poll at a statewide fund-raising event last September. He dispatched Bond, who directed Bush's 1980 Iowa victory, here full time and drastically increased his travel here. Bush has now campaigned in the state 38 days, 10 days more than he did in 1980.

Dole has held a small but steady lead in the Iowa Poll since last summer.

The gap between him and Bush closed to only 4 percentage points in December after Bush became the first candidate for the Republican nomination to embrace a treaty reducing the number of intermediate-range nuclear weapons in Europe, but it opened up to 15 percent after Dole endorsed the treaty and questions arose anew about Bush's role in the Iran-contra affair.

Almost all recent polls show the Dole margin over Bush in the double digits. The one released today was taken Jan. 25 to Feb. 5, with a margin of error of plus or minus 4 percent.

Staff writer Thomas B. Edsall contributed to this report.