NEW HAVEN, Conn., 5:15 PM — Around this time of winter every four years, the tens of thousands of college students spread around the state of New Hampshire tend to get an unmistakable burst of attention from presidential campaigns trolling for votes. But this year, the campuses are dark. Next week, students, in large part, will still be enjoying their Christmas vacations.

Usually, with New Hampshire residents selecting a nominee in late January, the state’s college campuses are back in session for the spring semester. But because of this year’s early primary date, this year will be different. Come Tuesday, only Dartmouth College will be up and running.

Last election, the New Hampshire primary was held on Jan. 27, when schools had already re-opened. But not this time around. The 11,000-student University of New Hampshire in Durham, N.H., for instance, will not re-awaken from its Christmas slumber until Tuesday, Jan. 22, a full two weeks after the primary is over.

That raises questions of whether student turnout in New Hampshire will plummet in this election — or whether candidates should even bother courting college students in the Granite State. In the 2004 Democratic primary, young voters accounted for about 14 percent of the total vote in New Hampshire, according to the Center for Information & Research on Civic Learning & Engagement.

“That is definitely a concern, especially with a lot of out-of-state students being registered [to vote] elsewhere and because the New Hampshire vote is so important,” Christine Snively, a 22-year-old University of New Hampshire graduate student and an organizer for Senator Hillary Clinton, told the Boston Globe last month. “Our main focus is just making sure that Hillary stays in their minds.”

That’s not to say the campaigns have given up on students entirely.

More than 900 New Hampshire college students have already filed absentee ballots in support of Senator Barack Obama, according to his campaign. Student groups in support of Obama are present on 12 campuses around the state, and volunteers from those schools have knocked on more than 17,000 doors and made more than 18,000 telephone calls on behalf of the Illinois senator, the campaign said.

Hillary Clinton, meanwhile, claims a dozen New Hampshire chapters of “Hilliblazer” student groups on college campuses.

Their work is not done.

At Dartmouth, more than 150 Obama volunteers will assemble on Tuesday to run a get-out-the-vote effort directed at students there, according to the campaign.

—Thomas Kaplan