HUDSON, N.H. — Hillary, Bill and Chelsea Clinton crisscrossed New Hampshire amid a driving snowstorm Monday, taking shots at Democratic and Republican rivals on the eve of the nation’s first presidential primary, looking to snap up a campaign that has been badly trailing in this state.

Plenty was at stake in New Hampshire, where presidential primary voters are “notorious” for making last-minute voting decisions, and the flurry of about 20 campaign rallies Monday reflected the uncertain nature of the 2016 race.

Clinton and Republican Donald Trump looked to solidify their national front-runner status. Sen. Bernie Sanders of Vermont hoped for a big win that could propel him as the contests move south. A handful of Republicans banked on New Hampshire to help them break out of the pack — especially Ohio Gov. John Kasich and New Jersey Gov. Chris Christie.

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Trump, criticized for not campaigning in the Iowa caucuses last week, capped a daylong push with a huge rally at a hockey arena in downtown Manchester. After tearing into his Republican opponents and Clinton, Trump ended a nearly two-hour pep rally by promising to help veterans, rebuild the military and provide effective health care.

“I hear we have a lead,” Trump said. “It doesn’t matter to me. We have something so special going on. We have to have a great victory. It is so important, because we are going to make America great again, greater, greater, greater than it has ever been . . . let’s have a big, big victory tomorrow!”

Along the trail, Trump called former Florida Gov. Jeb Bush a “stiff” and a “spoiled child” and harped on Sen. Marco Rubio’s (R-Fla.) widely panned performance in the last GOP debate.

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Pressing his case as the outsider who can make change, Trump said, “You have to understand what’s going on. A lot of time, you think . . . politicians are not smart people. They are smart people. But they are working for themselves.”

Bill Clinton, returning to the scene of his 1992 campaign turnaround, told a crowd at a high school gym here that his crowd was the best “change-maker” in the field.

“She doesn’t start with an ideological position and then make the facts try to fit,” the former president said of his wife. “She starts with the people.”

Earlier in Manchester, Clinton reportedly bashed Sanders for what he said was unfair criticism and painting Hillary Clinton as part of the “establishment.”

Hillary, once onstage, said she shared the same goals as Sanders — who has held a 20-point lead in most polls here. But he was “overpromising” about the costs of single-payer health care and free college tuition, she said.

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Earlier, Republican Sen. Ted Cruz of Texas was trying to build off his win in Iowa last week.

“Ask them, do they want a ‘campaign conservative’? Or a consistent conservative,” Cruz told tea party supporters at the American Legion hall here. Referring to rivals, he said voters should ask “where were you” amid important fights in Washington.

Democrat Bernie Sanders urged his supporters to forget about what the “establishment” tells them to think about elections and the “way things have to be” in society, the economy and politics.

“What we are doing is asking people to think big,” Sanders said at a small but packed downtown theater called The Palace. “If we can stand together, we can bring change.”

Every candidate in either party, save for Republican Ben Carson, slated multiple events around the populous southern part of the state, dashing from American Legion halls to coffee shops to country clubs to large arenas on the final day of campaigning.

With one day to go, it was hard to handicap how this might finish, said Marist College pollster Lee Miringoff. That’s in part because New Hampshire allows independent voters — who compose more than 40 percent of the state’s registered voters — to participate in the primaries.

“New Hampshire voters are notorious for deciding at the last minute,” Miringoff said.

The stakes for Trump are high. He led Iowa in the early polls, but finished second after skipping a debate and not making a strong last push there. In contrast, he slated four events for Monday in New Hampshire.

“He really has to win here,” Miringoff said. “Because up to now, his whole campaign is they love me. If it doesn’t turn out that way, the whole house of cards could crumble.”