I wrote a post recently about how the US population is moving toward the South (I'm one of those people since I was born in Indiana). One point I've made before is that some non-traditional markets have a remarkable number of "Yankees" or northern-born residents. I sat down and went through the official US Census data by metro areas. 

This reveals the number of "northern-born" in major markets. Keep in mind that these numbers are from the 2000 Census and are nearly a decade old--I expect that all of these numbers will be higher in the 2010 Census.

Northern-born (Northeast + Midwest) population for Southern and Western Metro Areas (NHL markets in bold)

1,886,000 Los Angeles
1,407,000 Washington/Baltimore
976,000 Phoenix
967,000 Tampa/St. Pete
916,000 S.F./S.J.
812,000 Miami
727,000 Atlanta
637,000 Dallas
570,000 Seattle
544,000 Orlando
532,000 S. Diego
453,000 Houston
404,000 Las Vegas
325,000 Norfolk
317,000 Portland, OR
238,000 Raleigh-Durham-C. Hill
237,000 Jacksonville
235,000 Charlotte
183,000 Nashville
161,000 S. Antonio
126,000 Oklahoma City
108,000 Memphis
98,000 Salt Lake City
74,000 New Orleans

The top 8 non-traditional markets all have well over half a million northern born population. The markets of Los Angeles and Washingon-Baltimore actually have more northern born residents than the Buffalo and Columbus metro areas which are located in the north.

The relative scarcity of Yankees in Raleigh and Nashville leave those two markets at a disadvantage. It doesn't mean they can not have a sustained fan base, but the task is more challenging in those two locations.

In the case of Atlanta, one out of every six native US residents was born in the north. In Tampa four two out of very five native US residents was born up north.

And just for fun here are the number of Canadians living in NHL markets:

68,919 Los Angeles

48,443 New York

41,963 Boston

36,791 Detroit

35,055 S.F/S.J.

25,937 Miami

19,226 Tampa

17,876 Phoenix

16,531 Chicago

15,775 Washington

11,717 Dallas

10,045 Atlanta

9,292 Philadelphia

8,555 Buffalo (surprising that Buffalo is so low on this list)

8,540 Minneapolis

4,722 Raleigh

2,958 St. Louis

2,663 Pittsburgh

2,518 Columbus

2,206 Nashville