With the New Hampshire presidential primary less than three weeks away, a new WBUR poll suggests Bernie Sanders might be peaking at just the right time. The survey of more than 426 likely Democratic primary voters finds Sanders in the lead, running well ahead of his three closest competitors: Joe Biden, Pete Buttigieg, and Elizabeth Warren.

This has been a good period for Sanders, who's been raising more money than anyone else in the race for the Democratic presidential nomination. Two national polls this week found Sanders and Biden ahead, while a number of polls have Sanders close to or in the lead in Iowa and New Hampshire.

The new WBUR poll (topline, crosstabs) is the latest. It finds Sanders is the choice of 29% of likely Democratic primary voters. That's well ahead of Buttigieg, who led in the last WBUR poll in December but is now in second place with 17%. Biden (14%) and Warren (13%) are virtually tied in third place.

Steve Koczela, president of the MassINC Polling Group, which conducted the poll, cautions that with almost three weeks to go until the primary, much can change.

"I wouldn't take these numbers to the bank," Koczela said. "But you've got to be feeling pretty good about where you stand right at this moment if you're the Sanders campaign."

The 78-year-old Sanders does particularly well with younger voters. According to the WBUR poll, he has the support of 52% of Democratic voters under 30. That includes 29-year-old Elizabeth Ahearn, an independent from Tuftonboro, New Hampshire, who said she is backing Sanders because he is pushing for Medicare for All."

"I have a variety of significant health issues," she said. "And everything's expensive. So it would be wonderful if we could have health care for all."

Ahearn believes Sanders can take care of another one of her priorities: defeating President Trump.

"It's very important to me," she said. "I nearly left the country permanently in 2016. I think he can do it."

While the WBUR poll is the latest evidence of a Sanders surge, it also shows that overall support for Warren has stalled.

"It's not really that voters have turned on her, it's just that she hasn't attracted more support over the last four to six weeks, or so," said Koczela.

In the WBUR poll last month, Warren had 12%; according to the new poll, she is up by just 1%.

Democratic presidential candidate Sen. Elizabeth Warren, D-Mass., speaks during a campaign event on Monday in Grimes, Iowa. (Patrick Semansky/AP)

The latest poll was conducted just after tensions between the Warren and Sanders campaigns broke into the open. Warren took issue with a Sanders campaign script that suggested she was only appealing to wealthy, highly-educated voters. (The new poll finds Warren's strongest support comes from those very voters.) Then Warren said Sanders told her in a 2018 meeting that a woman could not be elected president. Sanders denied saying that, which led to that now infamous post-debate disagreement.

"I think you called me a liar on national TV," Warren said to Sanders in a tense exchange that was caught on camera following the debate on Jan. 14.

"You called me a ...," Sanders responded, before cutting himself off. The two parted without shaking hands.

All this has put the issue of gender very much in play in the race, and could galvanize female support for Warren. There's also that long-simmering allegations of sexism against some of Sanders' supporters could pose a challenge for the Vermont senator. But, in fact, the WBUR poll found Sanders has the support of slightly more women than men.

The WBUR poll also found Biden getting his strongest support from older voters, leading with voters over 60. Edward Barton, a 70-year-old independent from Belmont, New Hampshire, told WBUR that he is backing Biden because of his experience.

"We need someone in there who has some common sense," he said. "[Biden] knows all the leaders and everything from being vice president, and that's what we need in there right now — especially now, after the mess that Trump's making."

According to the poll, Barton speaks for a large majority of likely Democratic primary voters who favor impeachment of President Trump and removal from office.

"Yes, a hundred percent," Barton said. "They should go in there ... and take him out in handcuffs."

The poll also found that big majorities of respondents believe Trump has made the U.S. less safe, and oppose a number of his administration policies and actions, including the assassination of Iranian Maj. Gen. Qassem Soleimani. It is hardly surprising that Democratic primary voters feel this way, and yet the poll found some significant nuance in opposition to Trump.

For example, while 93% say they have a negative view of Trump, a third of male Democratic primary voters say they approve of the way the president has managed the economy.

Pollster Koczela says these voters represent a significant opportunity for Trump's re-election campaign.

"Any inroads they can make among the Democratic base — among older voters, older male voters — on the economy, could be potentially very consequential."

New Hampshire, after all, is a swing state that Hilary Clinton won in 2016 by very few votes. No doubt it will be a battleground this year, as well.