CHARLOTTE, N.C. — President Obama doesn’t really need to suck up to the media, but Democrats here are taking no chances. The Fourth Estate’s finest, here to cover the Democratic National Convention, were treated to speeding-motorcade-style police escorts to a welcome bash hosted by the owners of the network Republicans love to hate: CNN. About a half-dozen police motorcycles and cruisers, with flashing lights and sirens blaring, led the way for a convoy of buses carrying reporters, photographers and others to the North Carolina Music Factory, site of the bash sponsored by Time Warner. The escorts then took the media...