WASHINGTON (AP) – A Republican critic of the Obama administration’s drone policy mounted a lengthy filibuster Wednesday to block Senate confirmation of John Brennan to take over as director of the CIA.

Senator Rand Paul of Kentucky took the floor shortly before noon. With intermittent support from Kansas Republican Senator Jerry Moran and Democratic Senator Ron Wyden of Oregon, Paul spoke almost continuously for over twelve hours.

After five hours of Paul speaking, Democratic Majority Leader Harry Reid tried but failed to move to a vote on Brennan Wednesday afternoon. Democrats then adjourned as multiple GOP Senators continued the filibuster late into early Thursday morning.