How Did Marco Rubio Get Attached to This Immigration Bill?

Three theories about Marco Rubio:

1) He has made a cold-eyed calculation that the approval of big Republican donors and Rupert Murdoch will matter more than the disapproval of talk radio and the conservative activist base;

2) He got played;

3) He was never really that excited about immigration enforcement in the first place: that message was for 2010, and this is now.