Excellent cartoon; Romney knows it’s his turn, and so do the voters.
I checked the insider advantage poll from 2008 right before the South Carolina republican primary.
In it, they sampled
2008
76.4% Republican
4.9% Democrat
18.7% independent
There is no indication they weighted the poll by party.
In this 2012 poll, they sampled
2012
66.9% republican
5.1% democrat
27.9% independent
They specifically left party affiliation out of those categories that they weighted
In this poll, Romney had a large advantage in independent voters; therefore, the more independents included in the poll, the higher Romney’s numbers.
The question, of course, is whether there actually are 10% more independents this year. If it were factual, one would think that category would have been weighted.
By comparison
In the 2008 democratic primary in S Carolina, they DID WEIGHT that sample for party:
0.7% republican
83.2% democrat
16.2% independent
2008 republican http://www.realclearpolitics.com/articles/docs/InsiderAdvantage_MajorityOpininoSCGOPJAN18IVRpoll.htm
2012 republican
http://www.realclearpolitics.com/docs/2012/InsiderAdvantage_SC_0115.pdf
2008 democrat
http://www.realclearpolitics.com/articles/docs/InsiderAdvantage_Majority_Opinion_SC_DEM_Jan_16_Poll.html