At the very least, I expect that a protest candidate of marginal status will enter the race and do fairly well in the Iowa caucuses (20-30%). In the end, she may win Iowa by less than 50-60%.
Well sure, if Sanders challenges her, then her margin of victory in either Iowa or New Hampshire being less than 50 points seems like a good bet. Sanders would air criticism of her from the left that most Democratic voters haven't been exposed to yet because they're not paying attention to the race. So I don't think he'd remain stuck at 2% by any means. There'll be *some* traction for his message in the party, so getting something like 25% or more in one of the early states is very doable.