WE HAVE one fearless forecast: New Hampshire will be on the receiving end of an awful lot of criticism in the next few weeks. Most of the criticism will refer more or less to New Hampshire's "unrepresentativeness" and most of the critics will turn out to have been supporters of an unsuccessful candidate in the Feb. 26 presidential primary.

New Hampshire is certainly no demographic microcosm of the nation. The state has more Republicans than Democrats and more small towns than suburbs. New Hampshire is the only state without either a state income or sales tax, which may or may not explain why New Hampshire is second only to Florida as the fastest-growning state east of the Mississippi.

But the fast rate of growth has not moved New Hampshire into the same class as the big guys. New Hampshire will cast only four of the 270 electoral votes needed to elect a president. In addition, New Hampshire is 99.5 percent white.

But it has not gone unnoticed among presidential candidates and their managers that nobody has been elected president of the United States, since 1952, without first winning the New Hampshire primary. Obviously a number of people -- like Henry Cabot Lodge, Edmund Muskie and Lyndon Johnson -- won the New Hampshire primary and not the presidency, but that will happen when you have two parties and only one president.

New Hampshire has turned back the challenge of every group or state that has tried to take away its first-in-the-nation status. Only a few years ago, the New Hampshire legislature wrote into state law the provision that the New Hampshire primary would be held one week before the primary of any other state. A supporter of the statute told his colleagues that New Hampshire would remain No. 1 even if it meant "voting at half-time of the Rose Bowl game on New Year's Day."

But there is a real case to be made for New Hampshire's special place in the nominating process. At a time when a candidate's media consultant is often more important than a candidate's energy record or program, there is something wonderfully old-fashioned -- and delightfully spontaneous -- about candidates' meeting voters face to face. Away from the briefing books and the prepared texts, the candidates are often interviewed by the voters and required to listen. New Hampshire provides its citizens with a unique opportunity to look the candidates over and to size them up. And that's all to the good.

Obviously, like voters in the rest of the nation, New Hampshire's voters can make some crazy judgments. Still, there is something worth preserving about an election where a candidate, with limited funds and less recognition, can persuade voters to support him by spending time in a Nashua legion hall or a Concord church basement, rather than spending money on a 30-second spot during "Three's Company."