Super PACs can raise unlimited money for a candidate, but are barred from coordinating directly with them or their team. Corporate-backed super PACs have already spent over $517 million during the 2026 midterm election cycle, Sanders noted in his letter. As the Vermont independent seeks changes to super PAC participation in Democratic primaries, he acknowledged that candidates will continue accepting PAC money in general elections without broader reforms. But the most immediate suggestion Sanders had was for the Democratic Party to prohibit super PACs from participating in primaries. "I urge you to take action and make clear that the Democratic Party will no longer maintain this corrupt system," Sanders wrote.