Mitt Romney is being called on to fire his national finance chair, Frank VanderSloot, over his anti-gay record.

The Human Rights Campaign (HRC), the nation's largest gay rights advocate, on Thursday launched a petition campaign against VanderSloot.

According to an extensive profile published last month, VanderSloot, the CEO of dietary supplements company Melaleuca, Inc., has a long history of using his wealth to back right-wing political causes. In addition to serving on the Romney campaign, VanderSloot is one of the largest donors to the pro-Romney superPAC Restore Our Future.

He's also been labeled a bully for threatening to file frivolous lawsuits against his critics.

VanderSloot bankrolled a billboard campaign in Idaho condemning PBS for broadcasting the documentary It's Elementary: Talking About Gay Issues in School. VanderSloot claimed the film hurts children: “If this isn't stopped, a lot of little kids will watch this program and create questions they've never had … little lives are going to be damaged permanently.”

The billionaire also donated generously to the campaign to approve California's gay marriage ban, Proposition 8.

HRC spokesman Fred Sainz told gay glossy The Advocate that Romney's association with VanderSloot runs counter to the candidate's stated position that he is opposed to discrimination against gay people.

Romney “can no longer get away with saying [that] he opposes discrimination against LGBT Americans while simultaneously working with someone as viciously anti-LGBT as Frank Vandersloot,” Sainz said.