THE NEWS MEDIA don't cover presidential campaigns the way they used to -- the way that Timothy Crouse captured in his best seller on the 1972 campaign, The Boys on the Bus. No longer do the star reporters remain on a candidate's plane for weeks and months on end, monitoring the rallies, talking to his staff, occasionally trading off with a colleague who is on another candidate's plane to get a feel for the opposition. The most prestigious reporters are often elsewhere now, "on the ground," as they say, in key states, talking with local leaders and plain folks, doing their own analysis (with or without the help of poll-takers) of what's happening outside the ingrown world of the airplane and the campaign bues and the candidate headquarters. In fact, the move toward the new style of campaign reporting had begun before Crouse wrote his book.

Elizabeth Drew's Campaign Journal is old- style, focused almost entirely on the day-to-day activities and strategies of the leading candidates and their advisers. As such, it has virtues, but also large defects.

Virtues first.

The book is crammed full of little capsules of insight, some betraying Drew's pro-Mondale views, to be sure, but gems nonetheless.

* On the body politic: "People react positively to confidence, serenity and optimism -- all marks of the Reagan political personality. We don't particularly enjoy seeing presidents fret."

* On Ronald Reagan: "The fascinating thing about Reagan is that he seems at once to have a very shrewd understanding of what he is doing with his rhetoric and to deeply believe what he is saying. . . . There is no disconnection and therefore he comes off as without artifice. We knew when Johnson, Nixon and Carter were faking it."

"Reagan is the maestro of the politics of blame."

* On Walter Mondale: "There is . . . a kind of hesitancy to Mondale, born sometimes of seeing the complexities and mixed implications of things, sometimes of sheer indecision -- which the public smells."

"The special interest issue is really a question about his strength."

* On Gary Hart: "People can impute to him what they want. Hart is, as of now, the ink blot candidate."

As in all of her previous books, Drew also displays an almost infallible ear for the spoken words we want to remember.

Feel like revisiting the rhetorical highs of the conventions? Want to check exactly what Jesse Jackson said in his electrifying apology to the Jews he had offended? It is all here -- not the full texts, but the sentences that still ring, interlarded with valuable judgments about the origins and purposes of the speakers and descriptions of how it is all going over in the hall. Wonderful reporting.

For such reference value alone, Campaign Journal deserves space on the bookshelf.

But the book is, quite simply, much too long, much too daily, much too full of minutiae that have lost whatever importance they may once have had. Is there really any point in our knowing now whether pollster Patrick Caddell was in or out of the Hart campaign's inner circle in a given week?

True, the entire book was originally written as a series of articles for The New Yorker, published every few weeks throughout 1983 and '84, and printed in book form without change. But even as magazine articles, Drew's reporting was found far too long and nonselective by many readers, including many who could certify themselves as political junkies. There is much to be said for rigorous editing.

Length is not the greatest flaw produced by Drew's old-style reporting, however. What is ultimately almost shocking about the book is the extent to which her concentration on the leading candidates leaves out so much of probable lasting importance in "the political events of 1983-1984."

The Jackson Campaign and, to a lesser extent, the Ferraro candidacy, almost do not exist in these pages.

It appears that Drew never detached herself from the Mondale-Glenn-Hart entourages in the primaries to follow Jackson for a day or two, to see with her own eyes the young blacks with their "Run Jesse Run" buttons, who had found a new self-respect and a new role model. Or to watch the registration drives bring thousands (including backlashing whites) into the political system for the first time. But she must have seen what the rest of us did (happily or not so) on the Democratic candidate debates: a black man holding his own, sometimes better than that, in intellectual combat with famous white men.

Surely, the nation is changed because of all this, but it is not recorded in Campaign Journal. The Jackson campaign is dealt with and analyzed simply in terms of the harm, as Drew sees it, done to the Mondale campaign.

Similarly with Geraldine Ferraro. Drew reports almost as rumor the large and incredibly enthusiastic crowds Ferraro pulled. When she sees the reaction for herself (at a joint Mondale-Ferraro rally in Wisconsin) she treats it almost as a freak show.

"The Queens accent is apparent and the people gathered here seem fascinated by her -- something new and unusual has landed among them. They seem to like her."

The Ferraro candidacy, like Jackson's, is treated simply in terms of what it means to the Mondale campaign. Drew concludes, on the basis of skimpy polling evidence, that it hurt, a highly contestable conclusion, particularly in view of the energizing effect her nomination had on women workers for the Mondale-Ferraro ticket -- a point nowhere mentioned.

Did Ferraro permanently change the political landscape? Those who doubt it should talk to Republican women. They are euphoric in their belief that Ferraro, by not blundering and yes, not crying or giggling, has eliminated the old barriers in their party as well as her own.

We have had much good reporting from Elizabeth Drew over the years. There is, in fact, much in this very book. Her account of the MX fight in the House of Representatives in early 1983, before the political season really got going, should be required reading for all who are covering the debate on the MX and the defense budget this year. It is a reminder of how good she can be at describing complex issues and contesting forces and of how much better Campaign Journal could have been if she had abandoned the candidates' planes and headquarters to cover -- and relate to the campaign -- the congressional battles over such issues as silent prayer in the schools.

One wants to shout at Drew: Ditch this outworn format, which probably was outworn shortly after Theodore H. White's Making of the President, 1960 told us all those things we'd never understood about what presidential candidates and their staffs really think about and do.

Since then, the best political books have probably been those that focused on a single element of campaigns, like Joe McGinniss' The Selling of the President, which told how advertising men and TV directors created a new persona for Richard Nixon in 1968. Or Larry J. Sabato's more recent work, The Rise of the Campaign Consultants: New Ways of Winning Elections, which unlike the others was not a best seller but should have been for what it told us about the new political techniques and technicians.

So ditch it. Keep an eye on these politicians, of course, because they'll find new ways to manipulate us. But find some other way to do it and then, keep going.