UNLESS THE vote for the far right-wing American Independent Party candidate is a good deal higher than expected, New Hampshire is going to elect former Republican Congressman Louis C. Wyman to the Senate tomorrow. Although all polls up until today have shown Wyman and his principal opponent, John A. Durkin, a Democrat who served as state insurance commissioner, in a virtual dead heat, a critical error of strategy by Durkin will probably cost him the election.

When the closeness of the original vote last November forced the establishment of a Senate select committee to review several hundred contested ballots, Durkin opposed efforts to have the first election voided and a new special election declared, preferring to cast his lot with the Democratic majority in the Senate, and on the committee. Since the first vote count in New Hampshire after the election had shown him the winner, though only by ten votes, this was not an unreasonable position; after all, winning by a little is still winning, as Lyndon Johnson proved in 1948. But when it became apparent that the condition of many of the ballots in question was going to make it impossible for the Senate to declare a winner, and even the Democrats, who badly wanted their party to gain the seat vacated by Republican hardliner Norris Cotton, began calling for a new election, Durkin refused to change his position. So Wyman was able to portray himself as the champion of letting the electorate make the choice, with Durkin appearing anxious to take the decision away from the people of New Hampshire. And when the inevitable happened, and the Senate finally decided to call for a special election, Durkin's original image as the spokesman for the little man, against big corporations and special interests, was pretty badly tarnished.

The second Durkin campaign has benefited only a little from what in other states would be a political godsend--Wyman is presently under investigation by the Justice department for his role as a middleman in the deal to make Mrs. Ruth Farkas ambassador to Luxembourg in return for a six figure contribution to the Committee to Relect the President in 1972. Wyman, who has virtually acknowledged the legitimacy of the charges, has been kept very much on the defensive on this issue, claiming simply, "I don't believe I broke any laws." But polls indicate that New Hampshire voters, who never regarded Watergate as too big a deal and who still feel that Nixon was driven out of office by a vindictive Congress, are not too riled up about the Wyman-Farkas connection.

THE CAMPAIGN has been extremely heated throughout, with each candidate charging the other with being a tool of out-of-state interests, Durkin calling Wyman a lackey of the big corporations, and Wyman accusing Durkin of serving "big labor," pointing to the AFL-CIO's $70,000 contribution to the Durkin campaign. Probably neither side scored any points with these too often repeated charges; nor is it likely that William Loeb and his Joe McCarthyite Manchester Union Leader will have a significant effect on the outcome. The Union Leader has however been making an all out effort to defame and misrepresent Durkin, and it's not unlikely that some voters may be swayed in Wyman's direction. The newspaper has repeated New Hampshire Governor Meldrim Thompson's analysis in an editorial saying that there is, "a clear distinction between a candidate (Wyman) who believes in the free enterprise system and one (Durkin) who would scrap that for nationalistic programs in a socialistic philosophy." Loeb (for Loeb dictates the Union Leader's editorial policy) also charges that Durkin is an advocate of socialized medicine, and an admirer of the Soviet Union.

In this election at least, the Union Leader is playing a relatively minor role, although the paper may have given Durkin enough of a scare to cause him to modify his views--he stated his opposotion to gun control laws last week, lest he come down on the wrong side of one of William Loeb's favorite issues.

President Ford's and Governor Ronald Reagan's pro-Wyman campaign swings through the state last week probably hurt as much as they helped. Ford's reception was particularly large and enthusiastic, and his on-the-stump appearances with Wyman last Thursday may well have impressed some. And Reagan certainly has his share of admirers in the state. But there are 31,000 unemployed in New Hampshire and Wyman's identification with the Ford economic policy, as it were, cannot have won him too many extra votes. In addition, New Hampshire residents are not generally impressed with big shot outsiders telling them how to vote or how to think, so despite the personal popularity of both Ford and Reagan, the net effect of the two visits was nil.

Durkin also still has a lot left of his image as a consumer advocate, which made him such a surprisingly strong challenger in the first campaign. As a popular and innovative insurance commissioner, he developed a solid state-wide consituency, which is now a good match for Wyman's established base of support in the southern part of the state--his Congressional district for ten years. The question then comes down to the swing vote--some 20 per cent of the electorate declared themselves undecided in a poll conducted only last week.

GENERAL PUBLIC INTEREST in the race coupled with President Ford's visit should ensure a large turnout at the polls. Essentially then, one of two things could happen with the undecided vote. A large number could opt for Carmen C. Chimento, the Independent Party candidate, in a protest vote, thus detracting from Wyman's total, and giving Durkin the victory. Chimento, who last week refused to welcome Ford, charging that the President is "a dupe of the Russian slavemasters," is trying to succeed where others have failed with his third party campaign. John Schmitz faired very badly in New Hampshire in the 1972 Presidential election, despite abundant coverage in the Loeb papers. And even George Wallace did less well than expected in 1968, a good indication that New Hampshire voters are likely to go mainstream and not risk wasting their franchise. The Chimento vote won't be higher than 5 per cent.

Which leaves the second possibility--that the undecideds will divide up pretty evenly between the two major candidates, giving Wyman only a slight edge, but just enough to win the seat. Durkin is very much past his peak, the machinations in Washington simply did not make him look good, and the chances of him winning are very small. Which means that Louis Wyman will finally win a long desired promotion to the upper house, and will have to bring his campaign against "the forces of big labor" to the U.S. Senate.