senators kyrsten sinema (d-az), rob portman (r-oh), maggie hassan (d-nh), shelley moore capito (r-wv), jon tester (d-mt), thom tillis (r-nc), jeanne shaheen (d-nh), john hickenlooper (d-co), bill cassidy (r-la), mark warner (d-va), mike rounds (r-sd), angus king (i-me), mitt romney (r-ut) and mark kelly (d-az) cosponsored the amendment. 