Newark Mayor Cory Booker on Sunday criticized the Obama campaign’s focus on Mitt Romney’s tenure at Bain Capital, setting off a new round of debate over the question: Is Romney’s private equity background fair game on the campaign trail? And is the Bain argument a winning one for the Obama camp?

We take a look in today’s Trail Mix video — and we’d like to know your opinion, too. Tweet at us with the hashtag #wptrailmix to let us know your thoughts.