MANCHESTER, N.H. — On the eve of this state's first-in-the nation primary, President Donald Trump was in a nostalgic mood, reviving some of his favorite lines of attack from his 2016 campaign as he looked to disrupt the Democratic contest here.

The president's stop Monday in New Hampshire was a return to the site of his first big win in the GOP contest in 2016, in a state that he lost by just a few thousand votes to Hillary Clinton in the general election — a result that Trump again blamed on people who he falsely claimed had been bused in to vote from neighboring Massachusetts.

As he had during his first campaign, the president returned to his incendiary claim that some immigrants are murderers and rapists, and he recited a poem about a snake that sneaked into a woman's house and killed her — a metaphor he has used in the past for immigrants.

"You're on the eve of giving us an opponent, and all these people want open borders," Trump said. He said many immigrants "are not exactly what we're looking for, OK? I mean, murderers, rapists and some other things. They're going to be poisoning our children with drugs."

The crowd responded with its own 2016 throwback — chants of "drain the swamp" and "lock her up," this time directed at House Speaker Nancy Pelosi, D-Calif. Standing on the sidelines of the rally were Trump's onetime 2016 campaign manager Corey Lewandowski and deputy campaign manager David Bossie, both of whom Trump thanked.

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Immigration remains a top issue among Republican voters, and Trump campaign advisers have been counting on the issue to fire up his base this year as it did four years ago. But at his rallies in recent months, Trump has focused much of his ire on impeachment and Democrats, making fewer mentions of his core issue.

The president's New Hampshire visit — which shut down several streets in the core of the state's largest city on the final night of primary campaigning — was the latest in a string of attempts to rival key moments in the Democratic contest.

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Trump has held rallies during Democratic debates and in Iowa days before the state's caucuses. On Monday, he sought to further influence the outcome.

"If you want to vote for a weak candidate tomorrow, go ahead. Pick one. Pick the weakest one you think. I don't know who that is," he said.

Trump, who faces only token opposition in his own primary here Tuesday, is also seeking to pick up New Hampshire's four electoral votes after having lost the state narrowly to Clinton in 2016. Republicans have 14 full-time staffers on the ground here, nine months ahead of the general election. By comparison, at this point last cycle, the Trump campaign had just one in New Hampshire.

New Hampshire voters will head to the polls while the results from the Iowa caucuses, which had former South Bend, Indiana, Mayor Pete Buttigieg and Sen. Bernie Sanders, I-Vt., claiming victory, are being contested.

Trump mocked Democrats' struggle to tally the Iowa results and sought to stoke division by accusing the Democratic Party of trying to steal the nomination from Sanders.

"I think they're trying to take it away from Bernie again," Trump said. "I think Bernie came in second. Can you believe it? They're doing it again, Bernie."

But the president didn't lob many attacks at his individual Democratic opponents, instead using broad strokes to define them.

"Democrats are now the party of high taxes, high crime, open borders, late-term abortion, socialism and blatant corruption," Trump said. "The Republican Party is the party of the American worker."