Senators rallying and whipping their colleagues to support the Iran agreement: 0.
Senators admitting that Iran has had no nuclear weapons program and has never threatened or been a threat to the United States: 0.
Senators pushing the false idea that Iran is a nuclear threat but indicating they will vote to support the agreement precisely in order to counter that threat: 16
(Tammy Baldwin, Barbara Boxer, Dick Durbin, Dianne Feinstein, Kirsten Gillibrand, Martin Heinrich, Tim Kaine, Angus King, Patrick Leahy, Chris Murphy, Bill Nelson, Jack Reed, Bernie Sanders, Jeanne Shaheen, Tom Udall, Elizabeth Warren)
Republican (and "Libertarian") senators indicating they will try to kill the agreement, thereby moving the United States toward a war on Iran: 54.
(All of them.)
Democratic senators inspired during the repulsive Republican debate Thursday night to announce that they will try to kill the deal (and would rather have a war): 1.