U.S. stock index futures fell in volatile trading late Wednesday, following a now-rare two-day rally by the Dow. Dow Jones Industrial Average futures YM00, -0.28% were down more than 120 points, or 0.6%, as of 10 p.m. Eastern, after swinging up and down a range of about 200 points. S&P 500 ES00, -0.61% and Nasdaq-100 futures NQ00, -0.56% also gave up earlier gains ane were each down around 1%. Earlier Wednesday, the Dow DJIA, +2.39% logged its first back-to-back gains since February, though stocks fell toward the end of the session as a roadblock emerged concerning the $2 trillion coronavirus stimulus bill in the Senate.