Bernie Sanders said Sunday that outside political groups that can raise and spend unlimited sums backing candidates for public office should be abolished — including those supporting his own bid for the White House.

But the Vermont senator stopped short of directly calling on Our Revolution, a political nonprofit he founded, to cease its efforts on behalf of his Democratic presidential primary campaign.

“I would think that we should end super PACs right now. So I would tell my opponents who have a super PAC, why don’t you end it? And certainly that’s applicable to the groups that are supporting me,” Sanders said.

The remarks, made during a candidate forum with New Hampshire Public Radio, are the first substantive response from Sanders after The Associated Press reported earlier this month that Our Revolution’s advocacy for his White House bid appeared to skirt campaign finance law.

For years, Sanders has railed against the torrent of money allowed to flood the political system in the wake of the Supreme Court’s landmark 2010 Citizens United decision. But he has saved special ire for super PACs, which is shorthand for super political action committee.

Our Revolution is not a super PAC. But the tax-exempt political nonprofit he founded in 2016 functions much like one — but without having to reveal who its donors are. Like super PACs, these nonprofits were similarly empowered to raise and spend unlimited sums after the Citizens United decision.

The only catch is that such groups must take steps keep their activities separate from the candidates they support.

Our Revolution, however, appears to be violating campaign finance law because the group was founded by Sanders, legal experts say.

The campaign finance act says that groups “directly or indirectly established” by federal officeholders or candidates can’t “solicit, receive, direct, transfer, or spend funds” for federal electoral activity that exceeds the “limitations, prohibitions, and reporting requirements” of the law. Those limits are currently set at $2,800 for candidates and $5,000 for political action committees.

It’s far from clear if the Federal Election Commission will take action. The agency tasked with enforcing campaign finance laws, does not currently have enough members to legally meet following a recent resignation.

Our Revolution, meanwhile, has taken in nearly $1 million from donors who gave more than those limits and whose identities it hasn’t fully disclosed, according to tax filings for 2016, 2017 and 2018. Much of it came from those who contributed six-figure sums.

The group has denied any wrongdoing.

A debate over big money in politics has riven the Democratic primary with Sanders and fellow progressive, Massachusetts Sen. Elizabeth Warren, leading the attack on rivals including former Vice President Joe Biden and former South Bend, Indiana, Mayor Pete Buttigieg, who have relied on big-dollar donors. Sanders has also attacked Biden for accepting support from a super PAC founded by his allies. During the 2016 campaign, he also criticized his rival Hillary Clinton for relying on their support.

But he was far more circumspect about Our Revolution on Sunday, chalking it up to a “broken” campaign finance system that he would try to overhaul if elected president.

“You’ve got groups all over the country that legally can do what they want. And I would be very happy to say and to urge an end to all that if other candidates do the same,” Sanders said. “So I am not in favor of these things ... But that’s the world that we live in.”

He also suggested there’s not much he can do to curb Our Revolution’s election activity, which includes turning out his supporters to the polls.

“The function of Our Revolution was to generate grassroots political activity, to get people involved in the political process and I think they’ve done a very good job at it,” Sanders said. Legally — and in fact, I have nothing to do with them — they operate absolutely independently of our campaign.”