Sen. John McCain's campaign is finishing a hard-hitting television ad highlighting Barack Obama 's ties to shady Chicago land dealer Tony Rezko, the one-time Obama patron who was convicted earlier this summer of fraud. A campaign official said that the decision to Go Rezko was Obama's. "He's opened the door to this," the official said. The ad will be released to network news divisions in time for their broadcasts tonight. Though McCain is widely perceived to to drawn first blood by attacking Obama's character, the official said that the difference between Obama's mocking McCain for his wealth and his shaky...