Presidential candidates have a long weekend ahead of them in New Hampshire, as they fight to gain support or maintain their lead in the polls ahead of Tuesday’s first-of-the-nation primary.

Democratic candidate Hillary Clinton is lagging behind Senator Bernie Sanders by about 14 points in the latest New Hampshire polls, though she has gained some ground since the Iowa caucuses.

Andy Smith, Director of the Survey Center at the University of New Hampshire, says it’s too early to draw conclusions: “we have seen large movements in New Hampshire polls in the last weekend of a campaign before.”

According to Smith, if Sanders does prevail, the magnitude of the win is what’s key:

“If she’s able to pull this into a single digit loss, well then [Clinton] can claim she’s like her husband, the “Comeback Kid,” who came back from deep double digits in 1992 to only losing by 8 percentage points.”

Clinton won the New Hampshire primary in 2008, and feels she can and should win again, says Smith. “But the magnitude of Sanders’ lead right now is such that – if it holds up like this – I don’t know how she would explain her way out of it.”

On the Republican side, Massachusetts Governor Charlie Baker finally waded into the primary election after months of neutrality to endorse New Jersey Governor Chris Christie.

Baker said he felt compelled to endorse Christie after the results of the Iowa caucuses and what he called the “slide of the party” to conservatism.

The endorsement isn’t likely to propel Christie from his low numbers (around 5 percent) in New Hampshire, however. Out of state endorsements don’t make much of a difference late in a campaign, says Smith, because “they don’t bring any political machinery with them…out of state endorsers maybe get a little bit of a story in the news one day, but it gets lost very quickly.”

Donald Trump still holds the lead in the republican race, followed by Marco Rubio. Ted Cruz places a close third.

Despite the snow falling in New England area Friday – and potentially on primary day – Smith doesn’t foresee the weather slowing down the candidates as they try to sway undecided voters.

“We’re seeing on the republican side that only 40 percent say they’ve definitely decided who they’re going to vote for. And on the democratic side, it’s just over 60 percent."

That means, Smith says, it’s more likely they’ll “slog through” and try and make their mark. 

To listen to WGBH Morning Edition host Bob Seay's full interview with Andy Smith, Director of the Survey Center at the University of New Hampshire, go to the top of the page.