North Conway, N.H. ? There’s a blanket of white on Mount Washington, a whiff of snow in the air down here in the valley. Some mornings there’s a rime of ice on the ponds, a thin sheet on the windshields. Everywhere in the North Country there is the sense that a change of season — dramatic, in some ways brutal, in all ways unavoidable — is in motion.

This is happening here not only in the distant hills but also in the political environment down below, where the change is perceptible, even powerful. Those who held sway have been swept away. A new series of struggles is all but under way.

One of the struggles is for fall — the very best season here, described by the New Hampshire poet Donald Hall as “the annual dazzle” — in its November effort to retain its precarious hold despite the advances of winter. The other struggle is more prosaic and political. This is a state of natural splendor, of course, but it also is a state of political engagement.

That political engagement — the new political season — is about to start, if it hasn’t already.

When the fall campaign began, New Hampshire was the bluest of states, the temptation almost irresistible to describe the political environment as being as blue as the skies in the Presidential Range. When it ended earlier this month, red skies of deep atmospheric change were everywhere.

The two Democratic seats in the U.S. House — gone. The Democrats’ 14-10 advantage in the state Senate — vanished, the Republicans now holding sway by an astonishing 19 to 5. The Democrats’ 222-176 margin in the state House — obliterated, the new margin being 298 to 102 with the GOP in unambiguous charge.

What this means for the national political picture is clear. The New Hampshire primary, for six decades the first in the country, will be conducted in an atmosphere that has been altered substantially. The Republican candidates’ challenge: transferring the energy and passion that transformed the state into a formidable political movement.

Some of this has started. Former Gov. Mitt Romney of neighboring Massachusetts retains a strong presence here and perhaps the strongest political organization. Gov. Tim Pawlenty, unrecognizable in any state beyond Minnesota, has been here several times. Former Sen. Rick Santorum of Pennsylvania, almost invisible in his own state, came here two days after the election — his sixth visit thus far, along with seven to Iowa and six to South Carolina — and soon will be back. Gov. Haley Barbour of Mississippi has made two trips here, Gov. Bobby Jindal of Louisiana one. Former Gov. George E. Pataki of New York, not exactly a political cover boy elsewhere, has a significant presence. The rules are different here.

All of which is why the 2012 presidential campaign is already stirring here.

“You can’t start any faster than the day after the midterm elections, and it started the day after the midterm elections,” says former Gov. John H. Sununu, the state Republican chairman and a onetime White House chief of staff. “Those who ran last time have residues of campaigns here. Those who didn’t run took advantage of the fact that we were trying to rebuild the party and came and helped.”

As a result, a new group of people moved into politics here, developed personal relationships and were infected with the political bug. Some of the big catches as the presidential candidates begin to assemble their staffs: six young people who worked for the state committee, became terrific political operatives and now are coveted potential shock troops for the 2012 primary.

Now that you have read this into a column on the 2012 presidential election and not encountered the name Sarah Palin, it’s time to remember that the former Alaska governor has not been in this state since a three-hour tour she made when she was the Republican vice-presidential candidate in 2008. She did endorse Ayotte, despite the Ayotte campaign’s efforts to keep its distance, and of course claimed some of the credit for her victory.

New Hampshire may have some surface similarities with Alaska — the snow on the surface in January, for example — but this may not be fertile territory for Palin. Unlike the Iowa caucuses, which are a strictly partisan affair, the primary here is open to independents, who in New Hampshire are the biggest voting bloc, comprising about two-fifths of the rolls. With no apparent contest in the Democratic Party, all those independents may surge into the Republican primary, changing the texture and nature of the contest in a way that presents great hurdles for Palin.

Palin’s role in the 2012 political calculus is, of course, the biggest variable, because implicit in it is the role of the tea party, the insurgency that provided so much energy for the Republicans even as it sucked so much attention from party regulars. Tea partiers have only now begun to influence the Republican caucuses on Capitol Hill, where they have endangered earmarks and grabbed the political momentum.

Their next target of opportunity is the presidential campaign. The question is whether they can further change a political environment that already is altered considerably — and whether the race for the White House becomes a race for tea party support in places like Iowa and New Hampshire.

— David Shribman is executive editor of the Pittsburgh Post-Gazette.