Though, Roll Call cautions, financial disclosure forms an unreliable source
                                
                                
                                    (Newser) -
                                    John Kerry leads Roll Call's annual list of the 50 richest members of Congress, with a fortune estimated at $231 million. But financial-disclosure rules make it impossible to get a complete picture of lawmakers' assets, so Kerry, John McCain (No. 13, with $20 million), and the rest of the top...