N.H.'s Surprise Photo Finish

ON this hallowed day in American politics, the New Hampshire primary, the top three contenders for the Republican nomination are bunched near the lead in most tracking polls. Who will win is anybody's guess.

But certain points are already clear: Sen. Bob Dole and firebrand commentator Pat Buchanan will keep going after New Hampshire, whether or not they win. Former Tennessee Gov. Lamar Alexander needs to do reasonably well in the Granite State - say, with percentage points in the high teens or low 20s - to convince potential donors that he deserves their money. Post-New Hampshire, his campaign finances are precarious.

Even if no candidate wins a decisive victory in New Hampshire, where each one finishes is crucial.

''Winning is winning, even by a point; winning is always a meaningful thing in New Hampshire,'' says William Schneider, a political analyst at the American Enterprise Institute who's in New Hampshire watching the action for CNN. Since the first New Hampshire primary in 1952, no Republican has lost here and won the party's nomination.

''If Dole wins [here], he's the nominee,'' Mr. Schneider says. ''If Alexander wins, he's the nominee if stories about his [personal] finances don't hurt him down the road.''

If Mr. Buchanan wins, he won't be the nominee, Schneider adds, because his appeal isn't broad enough to win a majority of delegates. And the majority of the party will coalesce to fight him. But if the populist commentator does win New Hampshire, say analysts, the No. 2 finisher in New Hampshire becomes key: He will become the stop-Buchanan candidate.

The GOP apparatus will do everything it can to make sure Buchanan is not the nominee, viewing his protectionist, isolationist views as outside the Republican mainstream. Charges of racism, fueled by the recent suspension of two campaign officials over their links to white supremacists, have also heightened Buchanan's negatives in polls and made him all the more unappealing to a majority of Republicans.

The weekend endorsement of Dole by Sen. Phil Gramm (R) of Texas - until last week a candidate himself and frequent critic of Dole's - is but one indication of how the Republican apparatus is pulling out all stops to make sure Buchanan doesn't win New Hampshire or the nomination. When Senator Gramm quit the race, he said he wasn't prepared to endorse anyone. But the party prevailed on him to act now.

Not that endorsements are the be-all and end-all. Dole already has the backing of 24 of the nation's 31 Republican governors, and still doesn't light any fires under GOP voters. But the party regulars are doing everything they can to carry their man across the finish line.

If Mr. Alexander, who finally has some momentum and a more youthful image than Dole, pulls an upset, it will put party leaders heavily banking on Dole in an awkward spot. But, says one analyst, ''they'll figure out a way to shift their weight toward Alexander.''

Jerry Carmen, chairman of the New Hampshire GOP, predicts Dole will win today. He says voters will reject Buchanan's ''dangerous extremism'' and realize that Alexander ''is just another Clinton.'' But he hedges.

''Buchanan might win in New Hampshire because the vote could be so split,'' says Mr. Carmen. ''But Buchanan is not going to get the nomination. The Republican Party will not accept what he says.''

''I'm one of those who believes Dole doesn't have to win in Iowa or New Hampshire, because it goes on,'' Carmen adds. ''If you recall, back in 1976, when Reagan almost beat Ford up here, that race went on until it was settled. If Alexander doesn't fall by the wayside, you'd have to beat him down the line. Buchanan you will not have to beat down the line. He'll be gone by convention time.''

After New Hampshire, the primaries come fast and furious: Saturday is Delaware, a contest that most candidates have ignored out of deference to New Hampshire's pride as the first primary. Then on Feb. 27 come South and North Dakota, where Dole is expected to do well, and Arizona, where Steve Forbes - whose numbers in New Hampshire are now as flat as his flat-tax proposal - has sunk a lot of money and could be strong.

Next comes South Carolina, on March 2, the first Southern state to vote. That will be a key test of all candidates in the South, including Dole, who is expected to do well in South Carolina. According to Schneider, Dole has a lot of support among religious conservatives there, including Gov. David Beasley.

''They want to be with a winner,'' says the analyst. Alexander, a former governor of a Southern state, also needs to show he can do well in his home region. The nine primaries of Super Tuesday, March 5, could seal the nomination for one of the Republicans.

In New Hampshire, turnout could be key to the outcome. If the weather is bad, that could help Buchanan, whose base of Christian conservatives, gun owners, and blue-collar workers are highly motivated to vote, says John Pitney, a political scientist at the Claremont McKenna College in California. Professor Pitney predicts a Buchanan win in New Hampshire.

But Clark Hubbard, a political scientist at the University of New Hampshire in Durham, sees two groups of motivated voters: the Buchanan people and the upper-income, civic-minded Republicans who he says will be motivated to brave bad weather to stop Buchanan, voting probably for Dole. He notes that Christian conservatives represent only 12 to 15 percent of New Hampshire's Republican electorate and are not the dominant force they were Iowa.