It’s right in line with every other poll out there, and kinda low for Trump vis a vis Reuters and Morning Consult, which usually have Trump 5-6 points higher.
I would expect that in poll, with a 4% margin of error, of only those people who are likey to vote in the republican primary, Trump and Cruz would be higher by 4 to 6 points each and Carson would remain about the same. I say this because the supporters of these three candidates seem the most motivated to go to the polls.