Ronald Reagan was kind of apologetic about the sanctions that have helped boost the local unemployment rate to l5 percent. Gee, whiz, fellas, he practically told a controversial rally in the Civic Center, I was aiming at the Soviets, I didn't mean to hit you.

He will, he promised, "enthusiastically" entertain motions from almost any floor about alternatives which might do as much damage to Moscow as to Peoria. Local fans, whose morale has been pumped up by rumors of an "October surprise" were disappointed.

"He didn't give us a thing," said a blond woman cabbie on the way to the airport the next day. "The farmers can sell to the Soviets, but we can't."

Peoria, the show-biz yardstick for solid bourgeois taste and values, is overrun these days by reporters from three continents. They are taking the temperature of the country's most conspicuous victim of both Reagan's economic theories and his foreign policy obsessions.

Bringing Reagan here was a dicey call for House Republican leader Robert Michel. On the one hand, it showed the Potomac clout which is the thrust of his campaign to retain the seat he has held for 26 years. On the other, as his young opponent, Douglas Stephens, noted, "It ties him right into Reagan, which is what I want to do."

Michel, 59, is in a state of profound embarrassment about what Reagan has wrought in this resolutely Republican area. Michel is ahead of the obscure challenger whom he is outspending by 3 to 1. But it bothers him that he must debate the upstart and that in his commercials he must brag -- awkwardly, for a card-carrying budget-cutter -- about the federal goodies he has brought home.

Almost everything about the presidential gala -- from the paid admissions, $5 to $15, to the presence in the cast of Charlton Heston and Pat Boone -- seemed to touch a raw nerve. The day before, the managers shifted the event to a smaller hall, a circumstance which caused a certain satisfaction in the union halls and Stephens headquarters.

Somewhat defensively, Michel told the flag-wavers at the rally that the razzle-dazzle "showed character, not callousness."

But just in case not everyone agreed, he had thoughtfully announced that he would pay for the police overtime involved in the inspiring event.

Michel knows that he is a handy club that the jobless and the disillusioned can use to beat Reagan over the head. He harps on Stephens' youth and inexperience. He calls him a "labor lawyer," a buzzword in the rural areas which account for half the vote. Stephens is a cool specialist in compensation cases, has blow-dried blond hair and monogrammed shirt cuffs.

Here, Republicans sympathize with Reagan's claim that the recession is not all his fault. But the sanctions -- which Michel first endorsed and later opposed -- re all his.

Caterpillar Tractor,the heartbeat of Peoria's economic life, is still. Only the business offices are open. Eight thousands workers were laid off as a result of the cancellation of a $90-million pipeline contract. Since then, more than 12,000 workers have gone on strike -- a strike, the union says, the company forced on them. At every block around the huge plant, pickets huddle around fires in barrels.

Stephens admits he is 10 points behind district-wide but ahead in the two most populous counties. What gives him hope is the fact that the romance between Ronald Reagan and blue-collar America is plainly over.

"Most of them deny it now, but nine out of 10 of them voted for Reagan," says Jim O'Connor, president of the huge UAW Local 974. "They thought he was after the big black woman on the welfare line -- he put everything in color -- now they think he is after them."

Around one of the barrel fires, six men were rubbing their hands against the biting wind. An inquiry as to whether any Reagan voters were present produced a small silence. Then one of them said, "If you don't use my name . . ." and confessed that he had indeed voted for Reagan and would again. "He's wrong on the pipeline, but I think he's doing what has to be done."

Across the street, a sign on the union hall door reads, "To get food stamps, you have to have children under 18." Inside a man who is, literally, big enough -- 6 foot 4 -- to admit it, says he voted for Reagan. "I thought he would straighten out the interest rate, bring her down, you know. I didn't expect him to take my job."

Tom Sargent, 29, a Republican, changed his registration to vote for Stephens in the primary. His Republican parents, Michel voters, will vote Democratic, too.

When Reagan finished his pitch, the ritual Republican balloons were released. It was all that prostrate Peoria got out of the visit. The whole world is watching to see if they will settle for balloons instead of jobs.