Sen. Bernard Sanders on Sunday accused President Trump, who frequently rails against Democrats and their “socialism,” of leveraging that same ideology to prop up his business and the rich.

Mr. Sanders, of Vermont, cited Mr. Trump’s use of tax breaks and subsidies to build “luxury housing in New York” and pass tax cuts in 2017 that benefited the wealthy and corporations while raising the national debt.

“The difference between my socialism and Trump’s socialism is I believe the government should help working families, not billionaires,” Mr. Sanders, an independent who is a frontrunner in the 2020 Democratic primary, told Fox News Sunday.

Mr. Sanders is hoping to gain significant momentum in the New Hampshire primary on Tuesday.

Yet Mr. Trump is eager to slam Mr. Sanders for his embrace of costly, government-oriented plans to provide insurance for all and tackle climate change in an aggressive way.

Mr. Sanders said he’s ready for the fight. He argues the U.S. already spends far too much on health care and that climate issues will cost far more down the road if the government doesn’t take drastic action.

“What do you think it’s gonna cost in food production when you have increased drought?” Mr. Sanders said. “We have got to act to save this planet.”

Still, he’ll have to shake unflattering attacks from the president, who has a big platform at the White House, on Twitter and in his trademark campaign rallies.

Speaking before the Super Bowl, Mr. Trump slammed Mr. Sanders as a “communist,” citing Mr. Sanders‘ trip to the Soviet Union around the time of his wedding.

“Obviously I’m not a communist. I presume the president knows the difference, maybe he doesn’t,” Mr. Sanders told Fox News Sunday.

He said his trip to the former Soviet Union was part of a “sister city” mission and involved local Republican figures, too.

“It gives me no pleasure to say this — we have a president who is a pathological liar,” Mr. Sanders said.

Mr. Sanders also continued to slam emerging rival Pete Buttigieg, a former mayor from Indiana, for taking money from Big Pharma CEOs and billionaires.

Mr. Buttigieg is running on a more central lane than Mr. Sanders and says Democrats need to rally support from a broad swath of America.

Mr. Sanders isn’t buying it, saying donations translate into influence.

“Does anyone seriously believe that you’re going to stand up to those powerful entities and represent working people?” Mr. Sanders said.

The young ex-mayor got in a retort on CNN’s State of the Union.

“Bernie’s pretty rich, and I would happily accept a contribution from him,” Mr. Buttigieg said. “I’m not a fan of the current campaign finance system, but I’m also insistent that we’ve got to go into this with all the support we can get.”