Massachusetts Senate candidate Shiva Ayyadurai has a catchy new campaign slogan: “Only a REAL INDIAN can defeat the fake Indian.”

The 54-year-old entrepreneur, who holds four degrees from MIT, recently plastered the slogan on a massive sign draped over a bus parked in front of an office building he owns about a mile from Sen. Elizabeth Warren’s home in Cambridge, Fox News reports.

The sign also features Ayyadurai’s headshot, alongside Warren’s mug wearing a Native American headdress.

Warren has faced criticism from Native American groups and others for listing herself as a minority – Cherokee Indian – during her time as a professor at Harvard Law School. Warren defends the move, which she insists did not benefit her professionally, based on family lore, and has refused to take a DNA test to settle the issue.

President Trump, for one, has taken to calling Warren “Pocahontas,” while Native American groups have increased pressure on the liberal senator to distance herself from the claim.

Ayyadurai first displayed campaign signs on the bus last March, initially with the message “Shiva 4 Senate/Be the Light,” then “Shiva U.S. Senate/Fight for America.”

But when he put up his new campaign slogan on March 17, city officials immediately threatened him with $300 per day in fines over alleged zoning violations.

“This is a political vendetta by city officials who are supporters of Elizabeth Warren,” Ayyadurai, who was born in Bombay, India, told The Washington Times.

“They didn’t say anything when we had the first sign,” he said. “It was only when we put up, ‘Only a real Indian can defeat the fake India,’ so it’s clearly trying to censor speech.”

Ayyadurai said the banner isn’t coming down, and he’s now suing the city in federal court over free-speech violations.

“We will not remove the slogan from our bus,” he said. “We will defend the First Amendment, and we will fight this egregious attack on the First Amendment, at any cost.”

Cambridge building inspector Branden Vigneault wrote in an April 5 letter to Ayyadurai that he received “a series of anonymous complaints” about the campaign signs, which cover both sides of the large bus.

Vigneault wrote that an inspection determined the signs were put up “without approvals and permits” and violate zoning.

Ayyadurai contends the building code applies to buildings, not buses.

And while he’s calling BS on city officials, Cherokee genealogist Twila Barnes has called BS on Warren’s family Indian stories.

“The problem with Warren’s story is that none of the evidence supports it,” she wrote in her blog Thoughts from Polly’s Granddaughter.