If she could get 60% of the vote against an incumbent Congressman in the Democratic wave of 2008, she should have no problem getting 70% of the vote against a nobody in what looks to be at least a slightly Republican year if not worse (luckily my state is insulated from this wave somehow).
That said, I really hope this doesn't hurt Michaud or Cain!
UNH's polls are prone to wild swings - in their poll they've regularly shown 20-point swings to and from each party during the last 6 months.
I'm expecting Collins to get in the high 60s myself.