CORALVILLE, IOWA -- If you put your ear to the tracks just before the Iowa caucuses, you could hear the Pat Robertson train coming straight at George Bush. In Cedar Rapids, about an hour up the interstate, the vice president held a desultory rally at which he showed issue fatigue. He proclaimed he would be the "education president." An audience of about 100 persons, warmed up by a cheerleading local politician shouting "Bush in '88," applauded politely and then meandered home. On caucus night, that's where they mostly stayed.

In contrast, Robertson drew about 300 persons to the basement of a motel here. There was no need for cheerleaders. While the Robertson people waited, they entertained themselves by singing "God Bless America." A farm wife, stout and tractor-like, talked about Robertson's effort in behalf of the farm poor -- his Christmas dinners, for instance. A farmer told a similar story. He was dressed in overalls, had a face as bleak as an Iowa winter and offered an endorsement of Pat Robertson as a man who cared for the less fortunate. The audience stirred.

With the arrival of Robertson, a thousand Instamatics seemed to flower. Children were held high by their parents, people pushed books at the candidate to autograph, and the room seemed to explode with heat. The dimpled candidate, natty in a blazer, flashed his winning smile and predicted he would carry Iowa -- and then the nation.

He had reason for confidence. Earlier, a Robertson organizer had asked the crowd how many had never before attended a caucus. Almost everyone raised his or her hand. A political Viet Cong had suddenly materialized. For George Bush, Iowa was Tet.

There is no telling how Robertson will do from here on out. New Hampshire is not expected to be his state, but then he has been underrated from the start. The strength he showed in Michigan was supposed to be a fluke -- and so were the results from Hawaii. His people hunker below the political radar line. Some have never voted before. Until caucus night, some were Democrats or not even registered -- a pollster's nightmare. The truth, the harrowing truth for the Republican Party, is that no one knows for sure the damage Pat Robertson can do.

There is a history lesson in Robertson. His medium is the contemporary one of television, but his message harkens back to the Great Awakening, revivalist movements that swept 18th- and 19th-century America. In a nation fixated on yuppies and enamored of the click of the computer keyboard, Robertson has cast his eye beyond the fern bar. Out there is a more traditional America, one angered and confused by modernity, yearning for old values, repulsed by abortion, fearing for the family and community, pious and, to an extent, paranoid. For instance, at the rally here Robertson exhumed that old bogeyman, the eastern elite -- cosmopolitan, powerful, intellectual and, for some reason, socialistic.

The Council on Foreign Relations was threatening Iowa. It would, Robertson said, "call for a socialist one-world government." He would fight it. He would ensure that socialism was not imposed on America, that the United States would not surrender its sovereignty. Never mind that no one has suggested such a thing. Never mind that few in the room knew what the Council on Foreign Relations is. These things do not have to be explained. The enemy is known and it has a face. "Give me the satisfaction of seeing Dan Rather have to announce Pat Robertson won in Iowa!" Robertson roared, and the audience roared back.

In the end, Rather had to announce no such thing. But Robertson did come in second to Bob Dole, a senator from the neighboring state of Kansas, and now the Republican Party must deal with a phenomenon of its own making. Latter-day George Wallace voters, no longer racist, have been summoned into the GOP by none other than Ronald Reagan. His emphasis on values, his opposition to abortion, his championing of school prayer and his courting of fundamentalist Christians have had their political effect. Robertson, who, like Reagan, was once a Democrat, is harvesting the crop the president has sowed.

Soon enough, the campaign will turn south. There the soil is rich in fundamentalism, and Robertson's appeal is biracial. (A co-host of his television show, Ben Kinchlow, is black, and so, for that matter, is his local organizer here.) George Bush may stave off Robertson in New Hampshire, but Dixie may be another matter. At heart a Brooks Brothers moderate, the vice president has neither the uniform nor the manner to command the troops Reagan assembled. In the cold Iowa night, they went over the hill.