Lots of good analysis of late polls out there, most accessible via TPM. Looks like there may be a late break toward Clinton, though that isn't a consensus opinion. My suspicion is that there is.
My prediction ('cuz what's the fun in watching polls and not trying to predict the spread?): Clinton by 10, 55-45. Like with every other major primary this year, just enough that the results falls within both campaign's goalposts of "victory."