Virginia's governor has thrown his support behind Mitt Romney. Gov. Bob McDonnell announced on Friday morning that he's endorsing the former Massachusetts governor. "As I have said throughout this primary process, we need a governor to serve as our next president,” Governor McDonnell said in a release. “America needs leadership and that's what governors do: they lead. Governors actually have to find solutions and bring all parties together in order to get results for their citizens – they can't just sit back and cast votes." Although pressed for months to offer an endorsement, McDonnell has steadfastly withheld commitment until now....