CEDAR RAPIDS, IOWA, SEPT. 10 -- If prevailing public sentiment about the U.S. role in the Persian Gulf is one of anxious support, then Iowa, with its anti-war tendencies and energy-dependent economy, falls heavily on the anxious side of that equation.

Foreign policy and energy issues have moved to the forefront of debate in the intense Senate race here between Democratic incumbent Tom Harkin and Republican Rep. Thomas J. Tauke. But the questions raised by both candidates deal as much with the Bush administration as with each other.

Harkin, a liberal in his first term, has emerged as a leading skeptic about, if not outright critic of, administration actions in the Middle East. While saying he generally supports President Bush's actions since Iraq invaded Kuwait, Harkin has challenged the president as much or more than any member of Congress over the last month.

Why, he has asked, is the United States going it so alone in the Persian Gulf? Why not send in a multinational U.N. peace-keeping force? Why are Americans footing so much of the bill? Why were reservists called up when only 5 percent of troops on active duty are involved in Operation Desert Shield?

Tauke, for his part, said he "can't buy" the suggestion by Secretary of State James A. Baker III of placing a long-term NATO-style force in the Middle East. Iowans, he added, do not want the United States to "get bogged down" in that part of the world. He has been especially critical of the administration's reluctance to use, or say it is preparing to use, the 590 million-barrel Strategic Petroleum Reserve to counteract oil price increases that are driven by market speculation and hit Iowa and the rest of the country soon after the Iraqi invasion.

How these questions and concerns will play out in the Senate race depends to a large degree on what happens in Saudi Arabia and Iraq between now and the election Nov. 6. But at this point, most political experts in Iowa say the situation appears to offer a slight advantage to Harkin, who leads polls by 10 percentage points.

"It depends on the twist these guys put on events, but if I had to make a prediction on which candidate could most easily capitalize, it is definitely Harkin," said Arthur Miller, director of the University of Iowa Social Sciences Institute. "He can play to the state's peace orientation. . . . I think in general people in Iowa tend to be somewhat less enamored with tendencies to get involved in other countries."

Tauke, a moderate and self-styled reformer on defense issues who voted against every bill increasing military appropriations during the Reagan administration, holds a realist's perspective on his current condition. Defining Iowa as "pacifist but internationalist," he said in an interview today that while Bush has high approval ratings for his handling of the gulf crisis, that "doesn't really translate to help for me" against Harkin.

"My feeling is that Bush cannot help me, but he could hurt me," Tauke said.

Harkin, in an interview Sunday, said his questions on Bush's handling of the gulf situation echo those that hundreds of Iowans asked him during a statewide series of town meetings last month.

"Everywhere I went, people had three questions: Why are we going it alone? Why are we paying for it all? And why are we calling up the reserves?" Harkin said. Still, he noted, there was a sense that something had to be done against Iraqi President Saddam Hussein "because he was a bully, and Iowans don't like bullies."

Tauke said Iowans ask him questions of a slightly different nature. "The anxiety is not so much about what we are doing but about what is going to happen next," he said. While Harkin has warned against the gulf standoff becoming another Vietnam "tunnel . . . with no light at the end of it," Tauke's point of comparison was not Vietnam but Nicaragua. Tauke was among the first House Republicans to turn away from the Reagan administration's support of the contras.

"The problem in Nicaragua was there was no light at the end of the tunnel," Tauke said. "We didn't seem to do what it took to win, but we weren't willing to pull out. In the case of Iraq, if we get bogged down in a long-term conflict, we will have real problems. If we are going to use the military in this case, we must make sure we win and win promptly."

Above all, Iowa remains the state "where the tall corn grows." As the harvest approaches, the gulf crisis is being felt most intensely by farmers who face stiff price increases for diesel fuel that runs their machinery and the liquefied-petroleum gas that is used to dry the crop. While this was a bumper corn crop year for most farmers, fuel cost increases of as much as 20 percent might strip away their profits.