The election of a Speaker would have gone to a second ballot — until one House Republican got cold feet:
A group of disaffected conservatives had agreed to vote against the Ohio lawmaker if they could get at least 25 members to join the effort. But one member, whose identity could not be verified, rescinded his or her participation the morning of the vote, leaving the group one person short of its self-imposed 25-member threshold. Only 17 votes against Boehner were required to force a second ballot, but the group wanted to have insurance.
Even with 24 members, the group would easily have been able to force a second ballot round, but the effort was aborted in frenetic discussions on the House floor.
Jonathan Strong’s article at RollCall.com is filled with juicy details.