Comment of the DayScowcroft, the GOP, and the Nuclear Deal: "Responsible Republicans acted...
:...when the Iran review act was passed in a version where the Iran deal could be approved on a practical basis by 1/3 + 1 vote of either Senate or House. It is the cowardly brave stance they often find on issues their base loves, but they fear would be revealed quickly as against to many national and their own political interests. The Supreme Court often chips in with timely work.
Even with majorities in both House and Senate they can all vote against it without having to find out the real consequences. In this case they rely on Obama to veto and Dems to sustain it. Obama could, I suppose, refuse to go along with the charade and threaten to not veto if Republicans provide no votes at all.