MANCHESTER, N.H. (AP) _ Commentator Patrick Buchanan cast himself Monday as the one true conservative in the presidential race, kicking off his GOP campaign with pledges to look out for ``our own country first'' and to rid America of ``the purveyors of sex and violence.''

Returning to the state where his insurgent candidacy stung President Bush three years ago, Buchanan said his 1996 campaign was ``for those who want to make our country America the Beautiful again.''

Buchanan portrayed himself as the champion of working Americans, and a crusader in a ``cultural war'' against lewdness and violence in the media, in music and in museums that ``welcome exhibits that mock our patriotism and our faith.''

Even as he formally announced his candidacy to about 150 supporters at the Manchester Institute of Arts and Sciences, demonstrators jostled him and invoked a darker interpretation of the rosy America Buchanan seeks to revive.

Four protesters leaped toward the stage shouting, ``Buchanan is a racist'' and waving signs comparing him to former Louisiana Ku Klux Klansman David Duke.

Buchanan reached out his arm and pushed one back from the podium before his supporters leaped to hustle them from the room. Demonstrator Ronn Torossian, spokesman for the Coalition for Jewish Concerns-Amcha, said the group had shadowed Buchanan on his last presidential campaign, alleging his writings and statements betray an anti-Semitic outlook.

``Now you know what we're fighting against in this country,'' said Buchanan. He seemed more subdued than usual in his subsequent remarks.

Flanked by his wife, Shelley, and sister Angela ``Bay'' Buchanan, he recalled his own Catholic-school childhood and lamented that today's schoolchildren ``are being poisoned against their Judeo-Christian heritage, against American heroes and American history.''

``Together we will chase the purveyors of sex and violence back beneath the rocks whence they came,'' he said.

Buchanan, who was a speech writer for President Nixon and communications director for President Reagan, most recently has been a host of CNN's ``Crossfire.'' He unnerved Bush in 1992 by winning 37 percent of the New Hampshire primary vote to Bush's 53 percent. He said Monday he had come back to ``resume the revolution we began here three years ago.''

However, he does not expect to get as many votes as he did then, when his showing was in significant measure an anti-Bush protest. He faces a bigger field of candidates, better financed than he is and campaigning on similar conservative issues.

Already Senate Majority Leader Bob Dole, Sen. Phil Gramm of Texas and former Education Secretary Lamar Alexander have devoted considerable time and resources to New Hampshire, which holds the nation's first primary. While they are aiming to raise at least $20 million, much of it from donors giving the $1,000 limit, Buchanan is relying on direct mail, radio and an 800 number to seek smaller contributions.

Bay Buchanan, who is her brother's campaign chairwoman, suggested he will have to come in at least second in New Hampshire and make a strong showing in the Iowa caucuses to keep his campaign going.

``The Buchanan brigades are not leap-year conservatives,'' Buchanan said, contending that some candidates turn to the right as presidential-election years approach.

After his announcement, he flew to Chicago where he boarded a motor home, which he will use to campaign through Iowa, the nation's leadoff caucus state, and then South Dakota. Buchanan addressed about two dozen supporters at O'Hare International Airport, telling them the Republican Party ``is becoming a Buchanan party.''

His strategy is to try and knit together support from anti-abortion forces, Catholics, gun owners, Ross Perot voters, term-limits supporters and those who share his belief that immigration and foreign trade entanglements undermine job opportunity for Americans.

``This campaign is about an America that once again looks out for its own people and our own country first,'' he said.

He said he would use the National Guard if needed to defend border states from illegal immigrants who ``break our laws, cross our borders and demand social benefits paid for with the tax dollars of American citizens.''

Although he is relying on anti-abortion support, he did not mention the issue in his speech.

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