Who can change the Electoral College map?

Michael Barone says that an Obama/McCain match in November could radically change the red vs. blue map of 2000 and 2004. The Boston Phoenix’s Steven Stark is more skeptical that Obama can compete in a large number of red states against McCain.

So how do the Democratic odds in specific states change with a Clinton or Obama nomination? D.C.’s Political Report bunches all the polls together, and below I’ve summarized the recent ones that show differences of more than a few points. These may mean nothing eight months from now, but they do suggest that each candidate has different geographical strengths, with Clinton firming up Democratic support in several big states and Obama running more strongly in mid-sized states in the Midwest and West (but not in the Deep South). The pollsters seem to agree that Missouri and Pennsylvania are close no matter who is nominated. There are no recent polls from Arkansas (Clinton would presumably win, but Obama is a big question mark), and Arizona seems solid for McCain; other than those, just about all the "swing" states are represented below.

ADVANTAGE: CLINTON?
Florida: Clinton behind by 6, Obama behind by 16 (Rasmussen)
Massachusetts: Clinton ahead by 9, Obama ahead by 2 (Survey USA)
New Jersey: Clinton ahead by 11, Obama behind by 2 (Rasmussen — but Quinnipiac has both ahead by 6 or 7 points)
Ohio: Clinton ahead by 10, Obama ahead by 3 (Survey USA — but Rasmussen and Quinnipiac have both candidates virtually tied with McCain)
Tennessee: Clinton behind by 7, Obama behind by 14 (Middle Tennessee State University)
Texas: Clinton behind by 4, Obama behind by 9 (Public Strategies)

ADVANTAGE: OBAMA?
Colorado: Clinton behind by 14, Obama ahead by 7 (Survey USA)
Iowa: Clinton behind by 9, Obama ahead by 17 (Des Moines Register)
Kansas: Clinton behind by 24, Obama behind by 6 (Survey USA)
Michigan: Clinton tied with McCain, Obama ahead by 8 (Rasumussen)
Minnesota: Clinton ahead by 4, Obama ahead by 15 (Survey USA)
Nevada: Clinton behind by 9, Obama ahead by 12 (Rasumussen)
New Hampshire: Clinton ahead by 2, Obama ahead by 13 (Rasmussen)
New Mexico: Clinton behind by 12, Obama tied with McCain (Rasmussen — but Survey USA has both candidates ahead of McCain)
Oregon: Clinton behind by 8, Obama ahead by 1 (Survey USA)
Virginia: Clinton behind by 10, Obama behind by 5 (Rasmussen — but Survey USA has Obama ahead of McCain)
Washington: Clinton behind by 4, Obama ahead by 15 (University of Washington — but Rasmussen has both candidates slightly behind McCain)
Wisconsin: Clinton behind by 12, Obama ahead by 1 (Survey USA)

UPDATE: Survey USA polls all 50 states and has both Clinton and Obama eking out Electoral College wins. Both carry the formerly red states of New Mexico and Ohio. Clinton pulls Arkansas, Florida, and West Virginia to the Democratic column but loses Michigan, New Hampshire, Oregon, and Washington. Obama carries Colorado, Iowa, Nevada, North Dakota, and Virginia but drops New Jersey and Pennsylvania. Take all this with a huge grain of salt, of course, but it does seem that they would be targeting different states as a nominee.