(Gage Skidmore)

Sen. Rand Paul (R-Ky.) will be plastered all over television tonight giving responses to President Obama's State of the Union address. But Tuesday morning, Paul had a different agenda.

Asked at a Washington conference whether a legal challenge to the NSA's phone records collection would reach the Supreme Court, the Kentucky libertarian said, "Yes, I think we will go."

"I'm suing the NSA," said Paul. "I would love anybody that supports that fight to sign on to my class-action lawsuit. ... The next step is, 'Is it constitutional to collect, with a single warrant to Verizon, can you collect 100 million people's records?'"

Paul's lawsuit is not the only one to tackle the NSA's surveillance program. Two high-profile federal cases have also come to differing conclusions about the legality of the spying. Some expect the Supreme Court to weigh in on the issue in order to resolve the contradiction.