The only states the relly matter in the 2008 election are listed below (how much):
All others are historically set one way or the other, and have little chance of changing regardless of how much time and money the candidates spend there.
Florida (27)
Ohio (20)
Georgia (15) - could quite possibly go (D) with Obama and severely fractured republican base, would be a huge upset
Missouri (11) - severely fractured republican base, would be a huge upset for (D)
Arizona (10) - almost certainly goes (R) with McCain
Louisiana (9) - probably (R)
Iowa (7) - liked Huckabee and Romney more than McCain, fracture could lead to (D)
Arkansas (6) - almost certainly goes (D) with Hillary, fairly important
Nevada (5) - went heavily with Mitt Romney, so if he loses, could go (D)
New Mexico (5) - probably (D)
West Virginia (5) - probably (R)
New Hampshire (4) - probably (D)
Remember, all the polls will show the candidates neck and neck nationally, which is worse than useless information. All that matters are the delegates that come from individual states. If Hillary, for example, could get an edge in Florida and Ohio, there would be a landslide democratic victory while the popular vote might still be 51/49 or less.
Home states historically carry a huge advantage regardless of the political makeup of the population. So Obama carrying Illinois is not important, since it's going to go Democratic anyway. Hillary carrying Arkansas is more significant, as is McCain carrying Arizona, an important swing state.
But looking at the data so far, the most significant thing I see is GEORGIA. Obama had a landslide victory in GA, while the Republicans split evenly three ways with McCain, Huckabee and Romney. That means a very significant chance of R dissatisfaction with the eventual candidate, and a good possibility of a narrow Obama victory in this Republican (but quickly becoming more Democratic as Atlanta becomes a youth destination) State. That alone could be a reason for the party to nominate him, quite honestly, since a victory in Georgia would almost insure a democratic victory in November (add an easy state like New Hampshire and you can afford to lose Flordia, Ohio, Iowa, etc., and still win.)
Florida and Ohio are, as always, the kingmakers. But I think this Georgia storyline is quite interesting. Let's see if the news picks it up. Another state to watch is Missouri. Then Iowa, then Nevada. Sorry everybody else, you don't really matter.