It is nothing if not intriguing. At first glance it overcomes the problem of unimpressive lightweight candidates with dubious policies, but all it does is replace them with unimpressive heavyweights with dubious policies.
Bloomberg is NOT a democrat, he is an oligarch and a terrible snob. His attitude towards farmers and tradesmen should disqualify him immediately. And the democrats are not those of the Bill Clinton, JFK era, [no one really knows Hillary's policies] so it is hard to see how it could work.
