I've never really thought that Obama has been more than mildly challenged for achievement of a second term. Romney is an exceptionally weak candidate that the Republican base has never warmed up to and his rightward efforts to try and win them over have alienated large numbers of independents.
Obama is firmly in control on both coasts and the urban Midwest, where most of the urban population centers exist. He is polling ahead in most, if not all, of the traditional swing states, including some that more frequently go for Republicans over Democrats.
The Republicans are left with racist and evangelically Christian rich, deep South and some Southern satellite Midwestern States, a few Western mountain and plains States, controlled by agrarian and resource extraction coalitions and a few benighted spots like Missouri and West Virginia where ignorance, intolerance and xenophobia are as deeply rooted in the gene pool and culture as hookworms are in their brains.
Put simply, Romney needs Ohio, Virginia and Florida. These are all States that most frequently vote for Republican Presidents. No Republican Presidential candidate can realistically win without all three. It hasn't usually been a problem for them. He is well behind in polling in all three of these States and trending lower, with Obama trending correspondingly higher. Chances are very low that things will change enough in the next month to turn things around in all three States.
In coming years, population shifts, generational change and increasingly sophisticated and empowered political organization on the part of racial and cultural minority factions are going to rob the Republicans of many more areas of political strength. The South will no longer be a stronghold for them. Texas and Arizona are demographic time bombs waiting to explode.