USA TODAY Poll: Impeached or not, Trump leads his Democratic rivals for another term

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Trump defeats Biden, Sanders, Warren, Buttigieg and Bloomberg in head-to-heads.

A third of Republicans support replacing Pence on the GOP ticket with Nikki Haley.

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WASHINGTON – President Donald Trump, the first modern president to face impeachment during his first term in the White House, now leads his top Democratic rivals in his bid for a second, a new USA TODAY/Suffolk University Poll finds.

The national survey, taken as the House of Representatives planned an impeachment vote and the Senate a trial, showed Trump defeating former Vice President Joe Biden by 3 percentage points, Vermont Sen. Bernie Sanders by 5 points, and Massachusetts Sen. Elizabeth Warren by 8 points.

In hypothetical head-to-head contests, Trump also led South Bend, Indiana, Mayor Pete Buttigieg by 10 points and former New York City Mayor Michael Bloomberg by 9.

Polls taken nearly a year before an election are hardly a reliable indicator about what the eventual outcome will be, especially when the other nominee hasn't been chosen. But the findings do indicate that impeachment hearings detailing what critics see as Trump's violations of the Constitution and his oath of office haven't undermined his core political support.

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The poll of 1,000 registered voters, taken Dec. 10-14 by landline and cellphone, has a margin of error of plus or minus 3 percentage points.

"Why waste the time going through all the stuff we're going through now?" asked Jason Mayo, 42, a truck driver and reliable Republican voter from Greenville, North Carolina, who was among those surveyed.

He predicted Trump would defeat impeachment "hands down" and then win re-election. "My 401(k) is doing better than it's ever done," Mayo said. "That's the truth."

But Elmer Ciers, 58, of Cincinnati, who is studying for a doctorate in business administration, said he was prepared to vote for any Democrat nominated against Trump. "I don't care" which one, he said in a follow-up phone interview after being polled. He said he was "scared for the future and our legacy" on climate change and other issues after Trump's first three years in office.

Trump's steady standing

Trump's standing remained remarkably steady regardless of his opponent, at 45% against Warren, 44% against Biden and Sanders, and 43% against Buttigieg and Bloomberg. That could be both good news and bad for him: A sign of the solidity of his support, but also an indication that he has a ceiling.

There was more variation among the Democratic contenders when they were matched against Trump. Biden received 41%, Sanders 39%, Warren 37%, Bloomberg 34% and Buttigieg 33%.

An unnamed third-party candidate received between 11% and 15% in the head-to-head contests – a factor that could determine who wins the White House.

"We know third-party candidates have minimal chance to win a presidential election but a high probability to make a difference in a state's outcome," said David Paleologos, director of Suffolk's Political Research Center. "Every ballot has third-party candidates who receive critical votes. When you give voters more than two options for president, you see how it impacts the major two parties."

In the survey, Trump's electoral strengths and weaknesses were apparent:

He won among male voters but every Democratic contender carried a majority or plurality of female voters against him.

He bested the Democratic hopefuls among age groups 35 and older, but he lost to each of them among voters 18 to 34 years old.

The president faces no significant primary challenge from former Massachusetts Gov. Bill Weld or former U.S. Rep. Joe Walsh of Illinois, who have announced campaigns for the Republican presidential nomination. They each received just 2% among Republican voters; Trump was backed by 88%.

More from the poll: Narrow majority opposes removing Trump from office if impeached

"I like Donald Trump's attitude," said Amy Locklear, 45, a retired teacher and Army veteran from Maxton, North Carolina. For many years a Democratic voter, she is now "leaning" toward the GOP. "If you say you're going to do something, he'll do it. He actually gets it done."

However, there was a wide willingness to consider replacing Vice President Mike Pence on the Republican ticket with former UN ambassador Nikki Haley: 34% of Republicans supported the idea; 37% opposed it, and 29% were undecided.

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A bump in undecided Democrats

Biden continued to lead the Democratic presidential field, at 23%. Also in the top tier of contenders were Sanders at 14%, Warren at 13% and Buttigieg at 8%. Compared with the survey taken in October, Sanders had ticked up 1 point, but the others had dropped a bit – Biden by 3 points, Warren by 4, Buttigieg by 2.

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Kathleen McMinn, 71, a retiree from San Tan Valley, Arizona, who was polled, is supporting 37-year-old Buttigieg. "I'm older; I generally would have voted for someone with more experience and time in office," she said. But now, "we need the youth in there."

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While she sees Biden at age 77 as "too old," she understands why he's doing well, as a "safe vote" and the candidate who has the best chance of beating Trump.

The number of undecided Democrats had spiked by seven points, to 25% – a signal that the race remains fluid. In fact, 57% of the Democrats surveyed said they might change their mind before the primaries and caucuses next year. Just 40% said their minds were firmly made up.

That may have helped open the door for one of the new contenders, Bloomberg, who finished fifth in the Democratic field, at 6%. That was more support that a half-dozen candidates who have been running for months, including Minnesota Sen. Amy Klobuchar, New Jersey Sen. Cory Booker, entrepreneur Andrew Yang, activist Tom Steyer and Hawaii Rep. Tulsi Gabbard.

Klobuchar was at 3%; the others were lower.

Billionaire Bloomberg also has been boosted by a flood of TV ads he's been airing. Nearly 6 in 10 of all those surveyed, Republicans and Democrats, said they had seen the ads. More than a third, 35%, said they were very or somewhat "convincing."

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