The chart above shows the public approval of the job being done by the 115th Congress in the two latest polls. Both of those polls have congressional job approval at only a dismal 10%, while disapproval is between 62% and 84%. Numbers can't get any worse that that. It makes Trump's terrible job approval numbers (in the mid to high 30's) look good -- and that's hard to do since he has the lowest numbers of any modern president.
The public wants solutions for the nation's problems, but they see a Congress that's unwilling to compromise to find those solutions. Instead, we have a Congress far more interested in fighting over ideology than finding solutions. The recent health care debacle showed that clearly.
Democrats and Republicans have always disagreed on the issues, but in the past they've been able to find compromises that moved the country forward (even though they didn't give either party everything they wanted). But the two parties in Congress are no longer willing to compromise -- afraid that their base voters will see the compromise as a surrender. But the public has had enough. They want solutions.
The polls also showed that while the public is not happy with either political party, they are a bit angrier with Republicans (who control both houses of Congress). And if the election was held today, most voters would prefer a Democrat in a generic ballot.
The Economist / YouGov Poll was done on July 31st and August 1st of a random national sample of 1,500 adults (including 1,329 registered voters), with a margin of error of 3.2 points.
The Quinnipiac University Poll was done between July 27th and August 1st of a random national sample of 1,125 voters, with a margin of error of 3.4 points.