The Republicans who do the best against Clinton, even if they aren't doing as well with the primary electorate this month, are Huckabee who leads by 5 at 48/43 and Walker who leads by 3 at 46/43. The other GOP hopeful with an advantage is Rick Perry at 45/44. Clinton is tied at 45 with Ted Cruz, Rand Paul, and Marco Rubio. Her leads come against Jeb Bush (45/44), Ben Carson (also 45/44), and Chris Christie (43/41.)
Even if Clinton trails Walker by 3, she's still easily the strongest Democratic candidate. Joe Biden would start out 9 points behind Walker (48/39) and Elizabeth Warren has a 10 point deficit (46/36). Overall the picture in North Carolina continues to suggest a very close Presidential race just like the state had in 2008 and 2012.
http://www.publicpolicypolling.com/main/2015/04/bush-reclaims-lead-from-walker-in-nc.html
