When the U.S. Constitution was created, the custom and expectation was that Representatives would be elected for two-year terms and that they would be in the Capitol representing their districts for only few weeks at the most -- each year. Hence, members of Congress kept and maintained their real jobs as business people, innkeepers, lawyers. etc. Accordingly, they had little or no expectation that their livelihood would depend on remaining in Congress for most of their working life.
Today's situation is entirely different. People run for Congress expecting a full-time job with generous compensation and perks most people can only dream of, not to mention a sizeable staff. As a result, today's members of Congress have become very dependent on their position as a way of life. And, after a few terms, most of them can no longer even envision any other job. They are a big deal to most people, particularly in their home districts, except in the Capitol, where most of them remain pretty obscure.
Consequently, it should be no surprise that when they are confronted with decisions on how to vote and behave in ways which might put their tenure at risk, they get pretty tense. The idea of losing an election and having to start life all over as an ex-congressperson must be pretty daunting. The choices are  do the right thing and loose the cooperation of their leadership,  do the wrong thing and lose the confidence of their voters or  do nothing, and hope for the best, but probably get the worst outcome as a gutless nobody.
This pretty much is what we are witnessing today for around 100 "moderate" Republican Representatives. Many are very decent people trapped between what's right and the Right. On the right they are threatened by primaries from well-funded tea party types. On the left, moderate Democrats, who appeal to moderate voters distrustful of the tea party. The result: a very real threat of losing a great job, a good income, and prestige with all expenses paid.
In some ways, these problems are not of their own making. It is a classic situational confrontation, a long time in the making, which badly needs to be dealt with, or along with them we might all lose our jobs/livings, if the current stasis takes us over the cliff.
One of the few options most of these conflicted folks have when/if they lose their House seat is to stay in DC as lobbyists and help make the overall situation even worse.
Now, here is a radical idea that would need a lot of horse trading to happen, but in a perverse and perhaps surprising way, could help fix the basic problem of job dependency undermining the country. In the larger scheme of things, it would not cost a lot of money, certainly as compared to the cost of the damage elected officials inflict by not doing their jobs properly.
Remember, too, that something similar is used in the Federal judiciary, where judges get their salary for life. This is meant to ensure an impartial judiciary, free from both deep-pocketed influence and fear of making an unpopular decision that costs them their job.
THUS: a sample plan for Congresspersons would be to provide a lifetime pension AFTER they have been elected at least five times and are 45 or older with some appropriate scale related to their salaries PLUS (very importantly) a lifetime ban on being a lobbyist.
The intended and hoped for effect of an arrangement like this would make it a lot easier for a lot of these House members to make their voting decisions free from the very corrosive, distracting and realistic pressures related to self-preservation.