Assuming House Republicans vote in a unified bloc, Democrats could afford to lose no more than 43 members to sustain an Obama veto.

But corralling 145 lawmakers to back the president on Iran won’t be easy, given the likelihood of divisive vote that many lawmakers say will be among the most consequential of their careers. …

After a Thursday morning meeting with Obama in the White House Situation Room, Rep. Adam Schiff (Calif.) — the top Democrat on the Intelligence Committee and another key undecided vote — told MSNBC that Obama is “well into the weeds on this issue” and appears intent on making the case to Democrats.