Carson and Fiorina's steep fall have been mostly taken advantage of by Cruz and Trump. They are clearly the two leaders, with Trump well out in front.
Rubio continues to make some ground, and even Bush climber a bit...but he is still distant, and has not begun to get even close to his numbers of five and six months ago.
I continue to believe that they should take the top four for the rest of the debates. Anyone below 6 or 7 percent should appear on the earlier, second team debates.