Funny... ask for Shakabuku, and the very next thing you read provides it for you.  In this case it's a blog post by Spivak & Bice... the two who have faces for radio... who happen to quote Russ Feingold's latest defense of the Incumbent Protection Act Campaign Finance Reform Act (subscription only):

Our legislation was about giving the American people a stronger voice in our democracy, and it worked. BCRA has helped return the electoral process to the voters. The corrupting influence of massive, unregulated "soft money" donations to political parties is gone, the parties are thriving without it, and, as we saw on Nov. 7, it certainly isn't easier for incumbents to stay in power.

Apparently Russ Feingold is as bad at math as he is at legislating.  When you crunch the numbers, as I mentioned in an earlier post, you find that 94% of incumbents were re-elected.  And that's in a year when Congress' approval ratings were at an all time low (in the 30% range), and when even Republicans didn't want to vote for Republicans.  And remember, the entire House of Representatives is up for election every 2 years, and the biggest "election wave of change" that the Democrats could come up with is 6%.  And that's not even considering how your law has set the barriers to entry so high, that no viable third party could ever come into play in this country.

Thanks to a combination of Campaign Finance Reform law, and district gerrymandering, which both parties love, incumbents are very very safe.  Don't fool yourself, and certainly don't lie to us about how incumbents can be defeated.  These days, the only thing that can get an incumbent defeated is making sexual advances to underage boys.  Is that the only measure we want to have for a "bad Congressman"?  If so, then our standards really are low.