No big bump occured from Oprah.   I find it amazing, myself, that Obama is not killing the field in his next-door state, where his biggest support and organization and thousands of volunteers are merely a couple of hours drive away.  

He really ought to be doing just as well in Iowa as Hillary does in New Jersey.  He's not.  That says to me his support has a definite ceiling, and he's not going to break it.  There are 50 states.  And she can carry more than he.