Hours before he headlines two campaign fundraising events in Boston on Wednesday, former Vice President Joe Biden pushed back against criticism by some of his top rivals for the Democratic presidential nomination for holding “high dollar functions” hosted by “corporate lobbyists.”

Biden, the clear front-runner right now in the Democratic nomination race, told Fox News “this idea of Biden’s the big donor guy, come on.”

SANDERS TARGETS BIDEN OVER TOP-DOLLAR FUNDRAISERS

Twice in the past couple of weeks, Sen. Bernie Sanders and his presidential campaign took aim at Biden’s top-dollar fundraising events from coast to coast.

In a fundraising email to supporters last week, Sanders spotlighted a campaign trip to Nevada that he made a day later.

“But I am not going to Nevada to attend a fundraiser hosted by a corporate CEO on the Las Vegas strip — I am going to Nevada to attend a rally with supporters and a town hall on immigration,” the populist independent senator from Vermont said.

While not mentioning Biden by name, it was clear Sanders was referring to the former vice president, who campaigned in Nevada three weeks ago. On that trip, Biden held a fundraiser at the Las Vegas Strip that was hosted by MGM Resorts CEO Jim Murren, a Republican. The CEO and other top executives of William Hill, the world’s biggest bookmaker, also co-hosted the fundraiser.

In a separate fundraising email titled “We risk falling behind” that was sent to supporters days earlier, Sanders campaign manager Faiz Shakir wrote that Biden’s “raising huge sums of money at large fundraising events all across the country. And these are not grassroots fundraising events.”

He spotlighted that “these are high-dollar functions hosted and attended by corporate lobbyists, health care executives, a Republican casino-CEO, and a union-busting lawyer among others.”

WARREN SLAMS BIDEN OVER 'SWANKY' FUNDRAISER

Another leading Democratic presidential candidate, Sen. Elizabeth Warren, also ripped Biden over his fundraisers. In an email to supporters in late April, the progressive senator from Massachusetts noted that the former vice president “hosted a swanky private fundraiser for wealthy donors at the home of the guy who runs Comcast's lobbying shop.”

Biden, after a campaign event Tuesday in Berlin, New Hampshire, pushed back.

“The stuff about Biden with the big contributors,” Biden told Fox News. “My lord, this idea of Biden’s the big donor guy, come on. I’ve eschewed any relationship with any PACs.”

And touting his grassroots contributions, Biden appeared to reveal for the first time the number of individual donors to his campaign, saying “we’ve had over 300,000 individual contributors. Average contribution of these is under $200.”

Biden’s been raising big bucks through small-dollar online donations – his campaign recently touted their online contributions and said those kinds of contributions made up the lion’s share of the whopping $6.3 million raised in the 24 hours after the former vice president announced his candidacy last month.

But Biden's also been holding some high-profile, high-end fundraisers. On his first night as a White House contender, he raised $700,000 at the Philadelphia home of a Comcast executive. He also hauled in big bucks at a Hollywood finance event and at two Florida fundraisers last month.

The former vice president’s expected to hold two major fundraisers in New York City on June 17, sources close to Biden’s inner circle told Fox News.

Fundraising was far from then-Sen. Biden’s wheelhouse in his unsuccessful White House runs in the 1988 and 2008 presidential cycles. But so far, the third time appears to be the charm, as Biden’s raking in big bucks both at traditional fundraisers with deep-pocketed donors -- which he's opened up to media coverage in a move for transparency -- as well as through online contributions.

BIDEN SAYS HOUSE PUSH FOR IMPEACHMENT COULD COME 'VERY QUICKLY'

The former vice president’s far from the only Democratic presidential candidate courting top donors. Sens. Cory Booker of New Jersey, Kirsten Gillibrand of New York, Kamala Harris of California and Amy Klobuchar of Minnesota are also holding closed-door finance events. And South Bend, Indiana Mayor Pete Buttigieg, a one-time long-shot who’s surged in recent months, is also competing for big money.

Sanders reportedly has decided to now hold in-person fundraising events and has hired an official to oversee such finance events.

Since jumping into the race in late April, Biden’s increasingly taken incoming fire from Sanders, Warren, and some of the other candidates in the historically enormous field of two-dozen Democratic White House contenders. Besides fundraising, Biden’s been criticized for his past support of free trade deals, for his 2002 vote in support of the Iraq War, and for taking an alleged “middle ground” approach to combating climate change.

Asked if he would return fire, Biden told Fox News: “I think the worst thing we could do is get into a match where we’re going after each other in the Democratic Party. So I’m going to try my best not to be negative relative to my opponents.”

And he said that “just like I’m not going to go down to Trump’s level when he starts his attacks, I’m not going to go down to anybody else’s level when they start attacks.”

But he said he would respond at times to “set the facts straight.” He added, “I’ll respond to assertions. I’m not likely to go and point out what they’re doing, which is sometimes different than what they say.”

Before heading to Boston, Biden made a last stop Wednesday morning in the first-in-the-nation presidential primary state of New Hampshire. The former vice president chatted with patrons at Chez Vachon, a Manchester eatery that’s a must stop for White House contenders. Biden was accompanied by influential state senator Lou D’Allesandro, a longtime friend of the former vice president.