Will Donald Trump win and if so, by how much?
The polls have had him consistently in the lead, some by 20 points or more.
The polls in Iowa had him in the lead too, and only a few people predicted he'd lose. He did.
And the polls in New Hampshire are much more indicative than predictive.
The problem they have is that many voters don't make their mind up until the day of the primary. And that causes upsets.
Trump needs a win here.
You can't keep talking about how great you're going to be and be rejected in the the first two places people vote.
The margin of victory is important, too. A slim three-five point win is still a win, but it might feel like a loss.
Will Marco Rubio's terrible debate performance hit him in the polls?
The Florida senator had a dreadful night in Manchester on Saturday.
Slammed for being inexperienced and inauthentic, he repeated the same Obama attack line four times.
That allowed Chris Christie to highlight that Rubio spoke in 25-second bursts approved by advisers and couldn’t stop.
I'm reluctant to draw a direct impact from the debates to the polls - remember most of us thought Donald Trump won the last Iowa debate by not turning up - but the Christie attack left Rubio wounded and vulnerable.
It certainly hit the momentum he generated from a better-than-predicted finish in Iowa.
Some polls here say he’ll finish third. If he doesn't, he has a problem.
How will the candidates who really started their campaigns in New Hampshire fare?
Three candidates - the governors, as they're known collectively - have banked on a good New Hampshire performance to kick-start their campaign.
But Chris Christie from New Jersey, Ohio's John Kasich and Jeb Bush from Florida are all chasing the same swath of voters.
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And they all see themselves as the real "establishment" candidate to take on the "upstart outsiders", Trump and Cruz.
They can't all be right. The percentage of votes will be important.
If there's one of two percent between them, they might think it's worth pushing on to South Carolina.
More than that, they'll have to rethink if their gamble worked and they have the money and support to go on.
Will Ted Cruz continue to attract big support?
There's no doubt that the Texas senator surprised many with his win in Iowa.
But he's been dogged since with allegations of dirty tricks by his campaign to skew the vote.
That plays into the worst perceptions of Ted Cruz as a man who'll do or say whatever is required to win; a slippery, dishonest career politican.
He was never going to win in New Hampshire.
Second or third would be a more than respectable. Lower and he has some problems as the campaign moves south.
Will any candidates drop out after New Hampshire?
Jim Gilmour has made one debate appearance, is polling at almost zero, and has banked on a good New Hampshire performance to get his campaign going.
But with little or no media coverage, a poorly funded campaign and few real supporters, it's hard to see how the former Virginia governor justifies going on.
The same can be said for Carly Fiorina.
She had her best moments in the race back in September and has failed to make any real impact or stand out beyond being the only woman in the Republican race.
It's always hard for candidates to step away but she may have no option.
Ben Carson also enjoyed some golden moments early in the campaign, but the neurosurgeon has been exposed as out of his depth on foreign and financial matters.
His answer to everything is to find the best brains available and ask them what to do.
His campaign is also struggling financially and organisationally.
He might keep going until South Carolina but many people will be asking why.
Source: Al Jazeera