Who would have thought that the biggest event of the campaign thus far is a non-event - that George Bush's "Quayle problem" would turn out to have no apparent negative effect on his effort to reach the White House?

That's what the polls are saying. They're also showing that most Americans did not have a less favorable view of Sen. Dan Quayle because he decided to serve in the National Guard during the Vietnam war. And a large percentage of the public is not happy over what it considers to be overkill in the press's coverge of the Quayle story.Was the media coverage excessive, or is this just a public perception? The Washington Post's chief editorial writer, the level-headed Meg Greenfield, puts it all in cool perspective when she writes:

"Dan Quayle has been paying the price not just for some acts of his own in the past that embarrass him as a candidate for national office, but also for a lot of other people's much worse acts he has nothing to do with, but which created . . . a super-suspicious, show-me press."

Negative coverage of Senator Quayle was supposed to hurt Bush. It did not. Ever since his speech at the convention that showed a "new," more outgoing, more aggressive Bush, the Republican candidate has campaigned with gusto.

At the same time, there was no evidence that Michael Dukakis gained ground during what some observers called the "Quayle hiatus." His campaign stalled. Dukakis kept trying to throw back the grenades being thrown at him by Bush - that he was a liberal and soft on patriotism, crime, and defense. Bush had secured, for the moment, the best-positioned terrain. Dukakis admitted Bush was setting the agenda.

Quayle said that all the controversy centering on him had brought in $1 billion in publicity. This sounded outlandish at first. But maybe he was right. In just a few days' time he had risen from anonymity to a widely known and readily identified public figure. Yet Quayle needs to convince voters that he's much more than a lightweight - even if that judgment doesn't seem, as yet, to be detracting from the Bush candidacy.

How will Quayle do against Sen. Lloyd Bentsen in the vice-presidential debate? Quayle will have the advantage of being perceived as the underdog. The accepted view of the public and experts is that the older, experienced Bentsen could wipe up on the C-student from Indiana. Quayle will have the benefit of very low expectations.

The election campaign has taken a surprising turn. Polls just before the GOP convention showed Dukakis with an 18-point lead. Now the polls as of this writing show Bush with a slight lead - a lead that was supposed to evaporate quickly after the convention.

Columbia University professor Henry F. Graff reminds us, in a New York Times column entitled "Maybe Bush Has Already Won," of the wisdom of James A. Farley, a Democratic tactician of 50 years ago.

Farley, writes Mr. Graff, "always argued that voters made up their minds by Labor Day." "Since his time," Graff continues, "electioneering has changed radically, but his axiom generally endures. We are not a nation of procrastinators when it comes to choosing a chief executive.

What prompted Graff's remarks was a late-August Gallup poll showing Bush four percentage points ahead of Dukakis. My own view is that this race is not set in concrete at this time; the voters for the most part still haven't made up their minds.