These charts are from the new CNN / SSRS Poll -- done between October 12th and 15th of a random national sample of 1,010 respondents, with a 3.5 point margin of error.
It shows that the Democrats would have a clear advantage if the election for Congress was held right now (51% Democrat to 37% Republican). That's a significant 14 point advantage.
That same poll showed that the public doesn't approve of the job Trump is doing (by a 20 point margin) -- and doesn't like the policies he has put forth (by an 18 point margin).
It's still more than a year until the next election, but the Republicans have a lot of work to do if they want to hang on to both houses of Congress -- and Donald Trump is not helping them at all.