Something's going on. Politicians at his level don't ever run counter the will of their political base like this, unless they're being coerced in some way, or paid off.
So-called 'Immigration Reform' has been beat down by angry American voters every time the Congress has tried to pass it. It's one of the most unpopular things they keep trying to do - and yet, they persist.
There's either a lot of money trading hands in brown paper bags, or dossiers being dangled on a string. Probably a combination of the two.