AUGUSTA – Sen. Susan Collins has become just the third U.S. senator ever to cast 6,000 consecutive votes. The Maine Republican hasn’t missed a roll call vote since taking office in 1997, and she reached the 6,000-vote milestone Thursday on two votes related to the Iran nuclear deal. She says the feat shows constituents that she’s committed to her job. Republican Chuck Grassley of Iowa has an even longer voting streak, with more than 7,400 votes dating to 1993. The late Sen.