So what is a speaker pro tempore?
Rep. Patrick McHenry, a Republican from North Carolina, was quickly named as speaker pro tempore of the House on Tuesday after McCarthy was voted out.
What does that title mean? It's quite simply somebody designated to preside over the House when the speaker is unable to do so.
After September 11, the House adopted a new rule making it possible to have a speaker pro tempore even if the speaker of the House is unable to name one -- or the speakership suddenly becomes vacant.
The rule was adopted as a measure to ensure "continuity of government" -- so that Congress would not be paralyzed after a terrorist attack. A speaker pro tempore has the power to lead, to pass emergency measures and even a declaration of war.
The position is supposed to be temporary, but there is no explicit limit on how temporary or when a new election must be held to elect a permanent speaker.
But, for now anyway, Republicans are operating on the premise that the House can convene and function even without an elected speaker.
One thing driving the temporary nature of this situation: The speaker of the House is in the line of presidential succession; the speaker pro tempore is not.
-ABC News Chief Washington Correspondent Jonathan Karl