Oprah has been very silent since Iowa ...
Someone may have paid her a visit ?
There's a much easier explanation than that: self-interest.
Oprah's a very bright businesswoman. She can see the danger of trying to get in the middle of a fight like this one.
If she took a political stance, there'd be no winning. Her "brand" is that she's a woman's woman. I think she'd lose a lot of her following if she allowed herself to be tarnished by the fact that she'd "gone political."
Yeah, sure, she's an unabashed Democrat, but her attraction isn't really political. To jump into a fight between Obama and Hillary would ruin her image.
Oprah misunderstood her audience. There are a lot of "conservative Christians" in her audience and many were horrified at her support of Obama. I am amazed how many women worship her and never had a clue how liberal she is.
She is very likable but I stopped watching her years ago when I recognized her "new age" leanings and what her true agenda was.