The 2008 election is on target to be the most harrowing election in recent memory. This will be the first Presidential election since 1928 that has no incumbents in the primary, with the 1952 election counting as a certain exception since Truman's name was indeed on the ballot, but he did not campaign. Harry had run out of "hell" to give anybody.
Additionally, there is massive and passionate anger in the voting ranks. We have the unpopular Iraq war in our laps, a budget surplus has been turned into the largest deficit in history, with what all figures point to as the least popular President stepping down from an eight-year reign - with impeachment cries dogging his heels, no less. The Republicans have lost more friends at this point than they ever have before. At the same time, we have massive dissatisfaction with the Democrat side, where we have had defeats at the hands of lame duck Democrat Presidential candidates and voted in a score of Democrats into the Senate and Congress who have since sat on their hands and done nothing.
So, the entire country is actually one big battleground. All assessments of the political map for 2008 have to take this into account. Being said, here are the states which are seen as the front lines of the Presidential race, and why:
Virginia: A decisive state on the Eastern side, it has recently gone from Republican to Democrat, but may be leaning back. The polls here have McCain ahead of Clinton by a wide margin of 51 to 42, but a tie between Clinton and Giuliani at 45% each.
Ohio: It is the "incumbent battleground", having decided the 2004 Presidential election.
Arkansas: This is where we get Bill and Hillary Clinton from, but also where we get Mike Huckabee. Arkansas is traditionally a Conservative state which votes Democrat most of the time. The votes this time will be split, with either Republican Huckabee, the most recent Governor, or Clinton, the former First Lady, emerging as victor. Polls have shown a slight leaning towards Clinton, but the Republican attention appears to be going towards Giuliani, not Huckabee.
Kentucky: This state is so divided that it can't help but be a battleground. The state went for Bill Clinton in 1992 and 1996, and for Bush in 2000 and 2004. Polls have shown Clinton leading Giuliani by four percentage points, but leading McCain by just one percentage point.
Colorado: Here we have another Clinton / Giuliani split, but it's a hair-split. 44 to 40 on the polls. The other factors that make it a battleground are the bordering of the Conservative Great Plain states, which tend to push it to the Republican side, and the large number of Hispanics in the state, which tends to pull it to the West Coast side and Democrat.
New Hampshire: It became a "swing state" in the 1990's, after having been solidly Republican before.
Indiana: It was mostly Republican up until 2006, when the state swung heavily to the Democrat side in the Senate race. The aforementioned Senate Democrats have done a great job of being clay pigeons since getting into office, however, so the state could veer back to the other direction. Polls currently show the state voting Democrat over Republican 37 to 32, but the state has not voted for a Democrat President since 1964.
Missouri: This state is the traditional bellweather for the rest of the nation, which is to say that if Missouri thinks it, the rest of the country starts thinking that way, too. Its central location both geographically and politically helps to give the status of a canary in a coal mine. The polls here have been largely in favor of Clinton, and it should be noted that the state just elected its first female Senator, Claire McCaskill, in 2006. McCaskill is ahead in the state's approval ratings, with even a third of Republicans saying they approve of her job so far, so this could give them a favorable impression of female politicians in general.