Exagerrated a bit there, but I assume that Hassan will run. If she decides against a run, this is a Toss-up and lean R at best. Anyway, my thoughts:
1. NH is no longer a swing state, it is trending to the left.
2. Ayotte is not that popular (even among Republicans), while Hassan is really popular.
3. Possible Hillary coattails because the GOP will almost certainly lose NH in 2016.
4. Ayotte is not moderate enough for a state like NH. She doesn't have the same reputation that Mark Kirk has.
I don't even think Hassan will run, but if she does, Ayotte shouldn't be counted out.
1. Wouldn't go that far yet. It tilts D, but it's not a full-on lean.
2. The Senate is more polarizing than the governor's mansion.
3. The right Republican (like a Romney-type or even Rand) can still win here, even against Hillary. Anything can happen.
4. I guarantee you, by the time 2016 is over, Ayotte will be seen as more moderate to NH than Kirk is to IL. And even then, moderation doesn't really matter in NH. We're very independent-minded, and if you make a bit of an effort to compromise, you'll do well here. She's probably closer to Judd Gregg and the Sununus than Susan Collins, but if you give off an air of pragmatism, you can get elected.