BTW, look how poorly Cruz does among Hispanics, blacks, and over $65,000 (i.e. college educated).
http://overtimepolitics.com/pollingdata/OvertimePolitics.comDec31-Jan3RepublicanPrimaryPoll-Michigan.pdf
"Overall, the Manhattan mogul commanded the support of 35 percent of the Republican and Republican-leaning registered voters ..." Note: this poll includes 'leaners' who may or may not vote Republican. Again not a reliable poll for future results.
A big question in the election is whether Trump supporters will change their minds. Our results show that half of Trump voters (51%) say they are absolutely certain they will vote for him. Another 3 in 10 Trump supporters say there is a large chance they will vote for him. Cruz and Rubio supporters, however, are not as certain that they will vote for their candidate. Just under half (49%) of both candidates' supporters say there is a large chance they will vote for their candidate but they are not absolutely certain.
January 05, 2016 Rueters 5 day rolling poll
644 RESPONDENTS
Donald Trump41.7%
Ted Cruz13.7%
Ben Carson10.6%
Marco Rubio8.2%
Jeb Bush8.1%
Wouldnât vote6.7%
Chris Christie3.2%
Rand Paul2.6%
Mike Huckabee2.2%
Carly Fiorina1.3%
John Kasich0.9%
Rick Santorum0.4%
Jim Gilmore0.3%
George Pataki—%
Lindsey Graham—%