On Thursday morning, shortly after George W. Bush had finished delivering his stump speech to a friendly audience that crowded into the comfortably heated downtown auditorium of a big insurance company, Gary Bauer stood on the icy front steps of the state capitol addressing two television cameras and five bundled-up reporters.

Shivering in his overcoat, while the cameramen adjusted their equipment, Bauer tried to lighten the mood. "I'm looking for the staff man who decided this should be an outdoor news conference," he said. "He will be fired."

As Iowans prepare to vote tonight in hundreds of precinct caucuses--the first official step toward the national convention nomination--the focus will be on the performance of the two lavishly financed men who are expected to dominate the field: Bush and Steve Forbes.

But for others actively campaigning here--Bauer, talk show host Alan Keyes and Utah Sen. Orrin G. Hatch, Iowa has become a survival challenge--and the occasion for asking what they have accomplished. Have they changed the agenda or pulled the leading candidates in that direction? Have they altered the likely outcome by the way in which they have divided the vote? If they are forced to the sidelines, what can they claim to have done?

Hatch, influential in Washington as chairman of the Judiciary Committee, has been unable to make much headway since jumping into the race last summer, later than all the others. In a reflective interview a few days ago, Hatch said, "I thought I was well-known," after appearing on hundreds of Sunday morning interview shows when Supreme Court nominations were pending, when major health care bills were being debated and, notably, when President Clinton was facing impeachment. "And being as well-known as I thought I was, I thought I would rise pretty fast in the polls. But without the money for 30-second ads, you have a hard time doing that."

National polls show Hatch hovering between 1 and 2 percent, and he has indicated he may drop out if he winds up last here tonight. That is not in prospect for Keyes or for Arizona Sen. John McCain, who has skipped Iowa to focus on upcoming primaries in New Hampshire and South Carolina. Keyes, a second-time presidential aspirant, has built a devoted following large enough to keep him in the race, whether or not he ever becomes a threat to the leaders.

Bauer, a former Reagan White House aide who ran the conservative Family Research Council before seeking the nomination, is ahead of Hatch in the polls but well back in the field. Like Keyes--a rival he refuses to criticize--Bauer is counting on the loyalty of his cadre of supporters to permit his underfinanced race to continue.

Bauer and Hatch have argued they have a better claim to the nomination than any of the front-runners--Bauer because of his 20 years of advocacy of conservative doctrine and Hatch because of his equally long career of pushing conservative policy on Capitol Hill.

Both say they are running to win--not to influence the front-runners. But both also say they have made a difference in the race. "China would not have been an issue if I had not raised it," said Bauer, who has repeatedly condemned human rights abuses there. "And I'm hearing my own words on abortion come back to me from other candidates."

Hatch said he thinks he did Bush a favor by telling him in an early debate that the Texas governor was light on experience and would benefit from spending eight years as Hatch's vice president. "I made the point that was on everybody's mind," Hatch said, "After that, you saw him get more serious. And I've continued to tell him, 'You have to be well-prepared. Gore will be tough, and you better be ready.' "

Both Bauer and Hatch said that the conservative social issue constituency of the GOP might have more influence if there were fewer candidates claiming to represent it. Bauer, who is openly skeptical of Forbes's assertion that he can lead the religious conservative movement, said, "If I emerge as the pro-life conservative, I'll be able to carry that message much further than he could, because of the consistency of my position. If Bush ever feels my breath on his neck, he'll respond more."

Outside observers gauge that the votes that go to Keyes, Bauer and Hatch might otherwise have been available for Forbes. Bill Dal Col, Forbes's campaign manager, conceded that is the "conventional wisdom" but said: "I doubt that's the case."

"Having them in, echoing many of the same points that Steve made, actually put more pressure on Bush than Steve might have done by himself," he said. "You can see the effect in the way Bush has been struggling to explain his abortion views."

When pressed to explain how the division of the religious conservative vote among several candidates could possibly have helped Forbes, Dal Col said, "Iowa is accustomed to having multi-candidate fields. That's not new to them."

He said he would have been happier with the lineup had "one more moderate Republican been running here" to contest with Bush from the other side of the party. "If Mrs. [Elizabeth] Dole had stayed in, I think she might have taken 15 points out of Bush. If McCain had competed actively here, he might have taken 25."

By that calculation, Forbes might have been within striking range of a first-place finish in Iowa. But Dal Col said he was not dissatisfied with the prospects now. "Whether they [Hatch, Keyes and Bauer] stay in the race for a while or not," he said, "there will only be three candidates really competing in New Hampshire and beyond--Bush, McCain and Forbes. And that is not a bad lineup for us."

Like Dal Col, Bauer argued that the fact Bush found himself pressed repeatedly in the last week on the fervor of his commitment to the antiabortion cause shows that antiabortion forces are influencing the race. He has said on each occasion that he wants to keep the same platform language--pledging support for a human life constitutional amendment--that Republicans have used since Ronald Reagan was president. But he has refused to say he would ask "litmus test" antiabortion questions of his running mate or Supreme Court appointees.

Karl Rove, one of Bush's top strategists, said that shows "an enormous consistency in his message. He is what he is."

Another Bush campaign official, insisting on anonymity, said that the only effect the trailing candidates have had on the race is to "make it more difficult for people to get their arms around what the major candidates are saying."

That has meant, he said, that Bush has had to rely more on paid TV ads to deliver his message than on the debates. "It's not a problem for us," because of Bush's generous finances, he said, "but it has meant that the debates focused more on issues important to the hard-core conservatives than to most other Republicans or to the general election voters."

"You've heard a lot about religion and abortion in the debates," the Bush adviser continued, "but not that much about education. And yet we know that education is No. 1 to most voters."

Two GOP pollsters said they thought the also-rans have had little impact on the race or public perceptions of the party. "There has been a certain dilution of the Bush-McCain race," said Robert Teeter, "but because because Bush started with such broad support and McCain turned out to be such a good campaigner, that still remains the choice the Republicans ultimately must make."

Linda DiVall, who polled for Elizabeth Dole, said, "I can see some places where they have made a difference. Senator Hatch, for example, put into play the criticism of McCain's campaign finance bill being bad for Republicans that Bush later was able to capitalize on. But overall, I'd say their impact has been minimal."