I think Hillary will have trouble in the western blue states like Colorado and maybe Nevada. The democrats there are more the "new age" democrats who wanna legalize marijuana and such, and not the union-loving, older crowd types you find out east. By 2016 I think it's going to be really hard for a Republican to win Nevada though, so it's really just Colorado she needs to watch.
What's kinda interesting is that with the current electoral college the way it is the GOP needs to make inroads into blue-leaning states like New Hampshire, Nevada, Virginia, and Colorado, while the Democrats can win more or less on their own turf. They can get to 270 while losing all the red-leaning states like Ohio, Florida, North Carolina, and Missouri.
If Hillary wins in Florida the GOP is almost completely shut out from getting to 270 regardless of how other states go.
With the way voting trends play out as long as the Democrats can win in either Virginia or Colorado getting to 270 should be easy. Since Hillary is the inevitable nominee and she's likely to face trouble in Colorado, it would be in her best interests to secure Virginia. Since Virginia is huge in military spending and Clinton is a big war hawk it should be easy to win here, also she'll have her right hand man McAuliffe as governor of the state.