Sen. Ron Wyden of Oregon, one of the most vocal critics of the NSA's surveillance infrastructure, revealed in an interview to Rolling Stone that he considered, however briefly, publicly exposing details of those programs from the Senate floor.
That response came after Wyden was asked about his now-famous exchange with Director of National Intelligence James Clapper, an exchange in which Clapper denied that the government collected data on citizens. Wyden, who'd given Clapper the question in advance, took action immediately afterward.
When the Director gave an inaccurate answer to the question, I had my staff call his office later on a secure line and urge them to amend his response. They decided to let his inaccurate answer stand on the public record, until about a month after the Snowden disclosures. Even then, they started off trying to defend his answer, before finally admitting publicly that it had been inaccurate.