Americans hold dim views of Congress and of House Speaker Paul Ryan, a new Wall Street Journal/NBC News poll finds, with favorable opinions declining since February. Nearly three-quarters of Americans disapprove of Congress’s job performance, up 12 percentage points since February, the poll found. Just one-fifth said they approve of the job Congress is doing, a drop of 9 points. Mr. Ryan (R., Wis.) is one focus of growing dissatisfaction, with 40% saying they view the House speaker negatively, compared with 22% who had a positive view—an 18-point gap. In February, unfavorable opinions outweighed positive ones by just 1 point.