Under Senate rules, any senator can try to pass a resolution or bill, but any senator can object and block passage.

Paul objected to passing the resolution after Democrats refused to drop their resolution and instead pass whistleblower legislation that he introduced earlier that day.

"I support whistleblowers, and I do think they have a role to play in keeping government accountable ... but what we have seen over the last few years is that we have a system that we should continue to refine," Paul said.