Senate 2008 Guru posts an analysis and introduction of State Rep. Grier Martin as a potential challenger to Senator Elizabeth Dole. He uses a lot of PPP data. Take a look.
It's important to note that the poll questions using Grier Martin and Kay Hagan were accompanied by short descriptions of their biographies. Therefore, comparing the poll numbers between them and other candidates like Brad Miller or Roy Cooper is like comparing apples... and uh, pears.
In a straight up poll- Elizabeth Dole vs Grier Martin with no other descriptors, Dole is going to be ahead by double digits but below 50%. What our polling shows is that if Grier Martin can successfully communicate his biography to the electorate, then his numbers shoot up significantly.