Before folks get too excited over Scott Turner’s announcement that he will run for speaker, consider the difficulty of defeating a sitting speaker. The speaker begins with a large number of supporters whose loyalty he has earned over the years. These supporters have long ago established themselves as leaders in the House. They already have the prime committee chairmanships locked up. No doubt there are some members who believe they deserve more than the speaker has bestowed upon them. Sure, some of them are jealous, some are looking to move up into a better position, but for the most part, anyone who has a chairmanship, or a vice-chairmanship, or a membership on a select committee, is likely to want to stay where he or she is. It’s hard to move up. The point is, there is a finite number of good positions in the House. They don’t come open every day. The average member, having achieved stature in the House, is not likely to throw away his career by switching sides.
The major factions in the House are the Speaker’s team (the insiders who perform the work), the tea party dissidents (the outsiders who plot and scheme and dream of the day when they can access the levers of power); and the Democrats. Republicans dominate the House, but there are currently 55 Democrats.

Here is the basic math: It takes 76 votes to be elected speaker, and when you start adding up the numbers, you have around 100 Republicans who make up the core of the Straus team. The committed members of the tea party, as the numbers showed in 2013, are relatively small, around 20 or so. Beyond that, the speaker always holds votes in reserve, and Straus has been careful to treat the Democrats as part of his team. As a result, he is all but impossible to defeat. The team plus the Democrats is an unbreakable majority of the House. No matter what Scott Turner or any other challenger to Straus does, it is extremely unlikely that there will be a successful challenge to Joe Straus.