Talk of a Mitt Romney-Rob Portman GOP presidential ticket, a leading pick among Republican insiders, picked up a flashy endorsement Wednesday from long-time political pundit and MSNBC Hardball host Chris Matthews. “Portman’s probably the best bet,” Matthews told the American Bankers Association convention of the Ohio senator. The former Carter speechwriter and top aide to legendary House Speaker Thomas P. “Tip” O’Neill, suggested that the second best pick for Romney would be Virginia Gov. Bob McDonnell. “I think he’s looking at Virginia and Ohio” as states Romney must carry to beat President Obama, added Matthews. It's an assessment GOP officials...