CONCORD – Now that Secretary of State William Gardner has set a primary election date, the campaigns of 16 mainstream Republican and Democratic candidates can launch their end-game strategies for New Hampshire.

Many counted on Gardner to pick Jan. 8, calculating how state law here played out against caucus and election dates in Iowa, Nevada, Wyoming and South Carolina. Michigan's court ruling yesterday was the last piece of the puzzle.

Campaigns now have less than six weeks to spend millions of dollars on television and radio ads, mail pieces and lawn signs. Candidates can lock in campaign stops, rallies, election night parties, and hotel room bookings.

"It does eliminate the uncertainty for them, but I think as time wore on, they were just assuming it would be Jan. 8," University of New Hampshire political science professor Dante Scala said.

Michael Dennehy, political director of Republican Sen. John McCain's campaign, said strategy here was already geared to Jan. 8.

"We had to make a calculated judgment some time ago for strategic purposes," he said. "We've been basing our entire New Hampshire campaign on it. This is just about the time period where we expect to pull ahead in the polls and win the primary." Gardner announced his decision late in the day, as airports and highways were clogging up with Thanksgiving travelers, including candidates. Their campaigns issued notably uncontroversial statements on the news almost as soon as the words were out of Gardner's mouth.

Sen. Hillary Clinton said, "I support New Hampshire's special role in the primary process, and I look forward to discussing the important issues in this race with Granite State voters over the next 47 days."

John Edwards said, "The New Hampshire primary is critical because voters ". . . take their responsibility seriously: They listen to the candidates, look them in the eye, ask them tough questions and size them up."

Sen. Barack Obama said state voters, "get to know the candidates up close -- to ask tough questions and see who is trustworthy to lead this country forward." He said he's organized a top-notch grassroots organization here.

The Republican National Committee voted recently to penalize New Hampshire by refusing to seat half its convention delegates if it holds its primary too early. The Jan. 8 date triggers the penalty.

Republican Mitt Romney promised help on that front in a statement.

"It is good news that New Hampshire's traditional role in the process has been maintained," he said. "I will work to ensure that all New Hampshire's delegates are seated."

Gov. John Lynch joined candidates in praising what he called Gardner's "steadfast work in protecting New Hampshire's first-in-the-nation tradition." With Iowa caucuses set for Jan. 3, votes will have little time to absorb results there before they have to vote.

"Will it really sink in with voters? That's the tricky question," Scala said.

"There are five days, and two of them are weekend days. We've never seen the two states so close before." Gardner said that even with the short time frame, he's confident town and city officials will handle the election in fine shape.

Absentee ballots, overseas ballots and ballots in towns where officials hand-count results all have gone out, he said.

"We're fine. There will be plenty of time," Gardner said. "Everybody has been in this together, and that's what makes this state so special."

He admitted his announcement cut things a little close, but not uncomfortably so.

"I was ready to wait longer," he said.