The 2018 Senate map was much more favorable to Republicans, who needed to defend only nine seats, compared with Democrats’ 26. Ten Democrats sought reelection in states President Trump won. Republicans were favored to control the chamber and possibly grow their 51-to-49 majority.
To retake the chamber, Democrats would have had to defend against formidable Republican challenges, win open seats in Arizona and Tennessee, oust a vulnerable Republican in Nevada and flip traditionally red Texas.
Top Democratic leader Nancy Pelosi is backing proposals that seek to address Democrats' concerns about the way the outgoing Republican majority ran the chamber, but also bipartisan complaints about more persistent weaknesses in House operations.