New Hampshire has held many hotly contested primaries for president, but this one will be marked by an asterisk in history books. The leading Democratic candidates were Hillary Clinton, the wife of a former president, and Barack Obama, the first black candidate to rise to this level of contention. She won, he lost, and pollsters are beside themselves trying to understand how they got it wrong.

There are those who take a skeptical view of all polling, and who can blame them given the ease by which day-to-day outcomes can be influenced? In a long campaign, there's an ebb and flow of events that polling can trace. That has certainly been true up to the climax this week. Polling has come a very great distance since the days of Harry Truman's victory over Tom Dewey when polls had Dewey winning handily, but the polling inaccuracy in this campaign is a first for everyone.

Polling is useful in a broad spectrum of ways beyond the political, but it is always a work in progress because of the dynamics of change.

Something like what happened in the New Hampshire primary raises skepticism because it's possible to strategize campaigns in order to influence a result. But what are we to make of it when all polling projections are uniformly wrong, as they were for the race between Obama and Clinton, when the same pollsters had it right for the narrow win by John McCain over Mitt Romney?

Possibilities for error in a poll are always possible, but the likelihood for this happening is bound to raise serious questions.

It's possible to phrase polling questions in ways that steer answers toward a desired result, but this kind of result defies common sense.

It's understood that some individuals polled do not give honest answers. But not everyone is polled and that would make it extremely difficult to produce what happened in all of the polling done in New Hampshire.

Races in both parties were highly contested, and it would seem that conditions affecting one party's outcome would be reflected in the other.

Was there some grand strategy held by Clinton supporters to be sprung at the last minute? With the press everywhere?

Could it have been that Clinton's name on the ballot was near the top and Obama's at the bottom that made the difference? Perhaps, but not to a great extent.

Could it have been that the absolutely sensational January weather on primary day brought out voters who might not have bothered had it been stormy? Very likely, but would they be like-minded?

What is indisputable is that both Clinton and Obama have powerful constituencies from depths never before sounded. She is the first woman, and he the first black ever to reach this level of consideration. That is not all that separates this Democratic primary season from that of the Republicans, but it certainly is of such a dimension as to energize Democrats as never before.

That casts this campaign in a different light from that of the Republicans. Only individual Democrats know how that contest resonates within them, but it is highly likely that the decisions of some in New Hampshire were not made until the last minute, long after polling data had been registered. It is reasonable to assume that this played a role among the undecided who finally opted for Clinton.

That, too, is speculation, but speculation is all we have until those we depend upon for research into such issues can explain what happened and why.

Bill Plante is former executive editor of Essex County Newspapers. His e-mail address is plantejr@comcast.net.