Sen. Bernie Sanders (I-Vt.) greets the crowd at a recent rally in Phoenix. (Charlie Leight/Getty Images)

WORCESTER, Mass. — Democratic presidential hopeful Bernie Sanders pressed his case that Republican front-runner Donald Trump is a divisive "demagogue" and verbally sparred with one of the billionaire's supporters during a pair of boisterous rallies Saturday in Massachusetts that drew overflow crowds.

Taking aim at Trump's proposed ban on Muslims entering the country and his call to deport undocumented immigrants en masse, Sanders urged his crowd to avoid “scapegoating minorities” and instead focus on “bringing people together to address the real issues we face.”

“We all know people are angry and they are upset for a lot of good reasons,” the Vermont senator said. “But what we have got to do is not let Trump and these other people divide us up. Latinos who are picking tomatoes for eight bucks an hour are not the reason that the middle class of this country is disappearing. Muslim kids who are going to schools studying to be engineers are not the reason we have income and wealth inequality.”

[Bernie Sanders raises more than $33 million in latest fundraising quarter]

Sanders’s appeal in a high school gym here came a couple of hours after he was heckled by a man wearing a Trump T-shirt at another Sanders rally in a packed auditorium at the flagship campus in Amherst of the University of Massachusetts.

As Sanders was rattling off statistics about wealth inequality in the country, the man started yelling “Shame on your Bernie!” from the third row.

“Here’s a Trump supporter worried about Mr. Trump’s money,” Sanders said, prompting boos from the crowd that quickly turned into chants of “Bernie! Bernie! Bernie!”

As the man was ushered out of the auditorium, Sanders continued: “I say to Mr. Trump and his supporters that the billionaires in this country will not continue to own this nation.”

[Bernie Sanders hits back after being called a ‘wacko’ by Donald Trump]

In recent weeks, Sanders, who faces Hillary Clinton in the contest for the Democratic nomination, has increasingly used Trump as a foil in his speeches. At the same time, Sanders has tried to make the case that he would better represent the economic interests of working-class Trump supporters than Trump would.

Trump has responded in kind, calling Sanders a “wacko,” among other things.

Massachusetts is among 11 states hold Democratic primaries or caucuses March 1, setting up what could be a pivotal day in the fight for the nomination if Sanders manages to upset Clinton in some of the earlier contests in Iowa, New Hampshire, Nevada and South Carolina.

At both events Saturday, Sanders, a self-described democratic socialist, drew crowds that far exceeded the size of the venue, and overflow areas were set up.

Nearly 3,400 people showed up in Amherst, while 3,000 attended the event here in Worcester, according to Sanders’s campaign.

Aside from the references to Trump, Sanders largely stuck to script, pitching an array of plans that include raising the minimum wage, guaranteeing paid family leave to workers, offering free tuition at public colleges and universities, breaking up the big banks and spending $1 trillion on a jobs program that would rebuild the country’s infrastructure.

Sanders begins a two-day swing through New Hampshire starting Sunday.