N.H. Primary Ads Take on Negative Air : Media: Three candidates mount attack-style commercials. Only Bush and Tsongas have kept a positive tone.

Nastiness is beginning to fill the air of the campaign for President.

Three days before Tuesday’s New Hampshire primary, three of the seven candidates are now running negative commercials--Republican Patrick J. Buchanan, Democratic Sen. Tom Harkin of Iowa and Democratic Sen. Bob Kerrey of Nebraska.

The toughest of the ads is Harkin’s; it makes an implicit statement about the tax policies of some of his rivals that is at best arguable and at worst flat-out wrong.

Only two candidates, President Bush and former Massachusetts Sen. Paul E. Tsongas have stressed the positive throughout their advertising, a sign of their status as front-runners as the campaign winds down.

Another candidate, Democratic Gov. Bill Clinton of Arkansas, has switched to a positive series of ads that emphasize his proposals after several days of running spots that pleaded with voters to ignore the distracting character issues that have been raised against him.

The advertising campaigns offer a clear expression of each candidate’s appeal--as well as his strategic problems--going into the crucial final weekend.

Harkin is running the closest thing to a pure attack commercial.

Complete with ominous music, the ad shows pictures of Kerrey, Tsongas and Clinton in black and white, while a narrator intones:

“These three Democrats are all saying the same thing: more tax cuts for the rich and big business. Create wealth at the top, they say, and it will trickle down to us. In 10 years, haven’t we learned? They never, never let it trickle down.’

“Only Tom Harkin will stop tax giveaways to the rich . . . invest in our people, rebuild this nation from the ground up, and put America back to work.”

The ad implies that Harkin’s three rivals support the economic policies of the Ronald Reagan and Bush administrations. The Harkin campaign defends that comparison by saying that Kerrey, Tsongas and Clinton have expressed support for some form of cut in the capital gains tax.

In fact, Clinton, Kerrey and Tsongas each support tax plans quite different from the one the Bush Administration is pushing. Their tax proposals would reduce the tax for people who invest in specifically targeted areas that are deemed to create jobs. The Administration’s proposal is a broad tax credit plan for all kinds of investments. The ad leaves a quite different impression.

Nor can Harkin unequivocally say that only he would invest in people or put America back to work. All the candidates make that promise.

The only major Democratic candidate not targeted in the ad is former California Gov. Edmund G. (Jerry) Brown Jr.

On Friday Kerrey even began airing an ad in response in which a narrator says “Tom Harkin is attacking Bob Kerrey, but he’s wrong on the facts.” The narrator, whose words are repeated in text on the screen, then accurately sets the record straight.

Another Kerrey ad takes a swipe at every other Democrat except Brown, whose standing in the polls is so low that his rivals don’t consider him a threat.

Over pictures of Kerrey on the campaign trail, a narrator says, “Bob Kerrey. A decorated war veteran. No one can question his patriotism. Able to win votes in the South and out West--he’s no regional candidate. A businessman who’s created jobs and a governor who wiped out a deficit--he’s different from the old-style Democrats who have failed to win again.”

The ad takes an unmistakable dig at recent questions about whether Clinton sought to avoid the draft during the Vietnam War. It also seeks to reinforce doubts that some have raised about Tsongas’ appeal outside his native New England. And it’s reference to the failure of “old-style Democrats” is a shot at Harkin, who styles himself the “real” Democrat in the race.

The ad also may be notable because it offers little reason to vote for Kerrey, other than that he is the least flawed of the field from a political standpoint.

Republican Buchanan has seven different ads on the air, and most of them--like his earlier spots--take hard aim at President Bush.

Several of them show New Hampshire voters talking bitterly about the President. In one, a Nashua woman says, “I don’t believe a word that the President says. I don’t believe anything that comes out of his mouth anymore. . . . And I’ll never, ever have the trust that I had for Mr. Bush when I elected him, when I voted for him. I’ll never get that trust back.”

But voters here also tell reporters repeatedly that they had actually begun to resent some of Buchanan’s incessantly negative ads.

What may be the final Bush campaign ad of the primary campaign--unveiled Thursday--seeks to take advantage of that, stressing a positive appeal.

Bush walks across what appears to be the Oval Office but is actually a book-lined studio adjacent to the White House. He looks directly into the camera as he tells New Hampshire voters: “I ask for your vote to lead America back to prosperity. And send Congress a message to pass my plan for economic growth. I ask for your vote to put our nation on notice that New Hampshire Republicans stand united to defeat the liberal Democrats in the fall.”

The campaign had produced ads critical of Buchanan’s opposition to the Gulf War, but decided in a meeting Thursday morning not to use them, White House sources said.

Tsongas has maintained a positive message. One ad shows him swimming, an attempt to reassure voters about the health of a candidate who had cancer.

Finally, Clinton’s campaign also began airing two new ads Thursday trying to return to a positive message about policy.

For the last four days, Clinton has aired a sometimes dizzying array of ads, most of them asking voters to ignore tactics designed to “distract and divide” the country, and denouncing “the tabloids,” a reference to a supermarket tabloid that made allegations against Clinton of marital infidelity.

There was sufficient confusion that WMUR-TV, the state’s lone network affiliate, even aired one ad Wednesday that the campaign had delivered but then decided it did not want aired. The ad was a series of quotations from newspapers noting, among other things, that the supermarket tabloid that accused Clinton of marital infidelity had paid sometime cabaret singer Gennifer Flowers to make that accusation.

In one of the new ads, Clinton looks just to the left of the camera and says, “Our whole economic future is on the line in this election. In the 1980s, Reagan and Bush encouraged greed, poverty exploded, the middle class suffered. Now it’s time to put our house in order and to take care of our own. That’s why I’ve offered a bold national economic strategy for jobs, health care, training our workers and college loans for everyone. . . . “

Times staff writer Douglas Jehl contributed to this story from Washington.