Bill Bradley is on the road, a bus for himself, his wife and his staff, another for the press. He stops at towns like this one where, with apologies to Walt Whitman, he hears America whining. What is his position on health care, veterans' benefits, the family farm and, even, breast feeding? The questions are micro, but Bradley is a macro man, crusading to abolish child poverty, soft money and bigotry, and to bring health care to everyone. His staff more than once refers to Robert Kennedy. This bus is heading back to the future.

At least Bradley thinks so. He paraphrases the first-century Jewish sage, Hillel: "If not now, when? If not us, who?" For Bradley, the man and the moment have come together. His liberalism, his idealism, are finally in sync with the Democratic Party's if not the nation's. This is how he sees things anyway, and only the voters can tell him he's wrong.

Whether that will happen it is too soon to say--although his prospects do not seem particularly good in this state. The average age of an Iowa caucus voter is 51. They are Democratic Party regulars, union members. They don't dream, they plan, and if the polls are right, most of them are planning to vote for Gore.

Bradley's campaign poses a really interesting question. It is not whether he, and not Al Gore, is right about the financing of health care but whether he is right about his party and country. Could it be that the great era of centrism is over? Are we ready for the final assault on child poverty, on health care--racism and the gun culture to boot? Could it be that with good times and a national treasury busting like Scrooge McDuck's vault, we are prepared to move left?

"I believe in fixing the roof while the sun is shining," he says repeatedly. Maybe Bradley is on to something. His own campaign has done exceedingly well. He's given Gore more of a fight than anyone (okay, I) would have predicted. He's about even in fund raising and neck- and-neck in New Hampshire. Ask his young volunteers what attracts them to him and they say his call for altruism, to clean up the money-besotted political system and not--by implication--to be Al Gore.

This, above all, remains his greatest asset. He is the non-Al, fluid in his movements, at ease with himself, certain of his convictions, unburdened by years of being a ventriloquist's dummy on Bill Clinton's lap. Something about him still suggests the athlete's gift of taking in the whole court and sensing--in a way that no one can explain--where every other player is. When he says he took time off to study the country, to learn about Silicon Valley and the new economy you suspect that he sees something the ordinary eye cannot.

But Bradley is neither a Lyndon Johnson nor a Kennedy. In the Senate, he was hardly a leader. On the stump, he can be occasionally moving, but usually he lacks intensity. He was clearly touched by the hardship stories he heard on a picket line in Des Moines, but his retelling of them was flat, emotionless. Worse, he can be coldly dismissive.

In a recent debate, for instance, he punted Gore's question about why he voted against a 1993 flood relief bill in the Senate. With a flooded-out farmer standing in the audience, Bradley coldly said, "This is not about the past, this is about the future"--a line auto insurance companies might try after a collision. In fact, Bradley had good reasons for his vote, which he later explained. But in an interview with me, he did not seem to appreciate how callous he appeared, nor how his supposedly nonconventional campaign handled the matter with conventional spin.

The occasional disconnect between Bradley's ideals and his demeanor is hard to reconcile. Yet he remains right and bold about so much--child poverty, gun control, racial harmony, universal health care and, of course, campaign finance reform. It's hardly clear, though, that he's the guy to do the job. As Hillel might put it, the "when" could be now. But the "who" is still an open question.