Sorry, incorrect again.
Perry led Romney up until the last week of September in 2011. Then Romney and Cain traded places until Veterans Day. Then Gingrich led all of the polls until 2012.
Polls at this point in a race are very fluid, have questionable sampling data, and are entirely reliant on name recognition.
Trump recognizes he needs to beat back #2 only. He isn't worried about #10. Moreover, he has money that Cain and Gingrich only dreamed of having, and has far more money than Carson and Cruz put together. Finally, the states where Carson is #2, quite often the next state up has someone else in #2 slot. So in terms of delegates, it's pretty much a done deal.