The job approval rating of Congress, while still atrocious, has managed to improve slightly in the last few months according to Gallup. Currently 17% approve of the job Congress is doing and 79% disapprove.
Congress actually hasn’t done much of anything of substance in the past month that should improve the popular image. So it seems the main reason Congress has become slightly more popular is simply that they haven’t actively done things to piss off the electorate recently.
It is a sad statement about how we have been running our legislature that it is least unpopular when it is basically doing nothing.