WEST PALM BEACH — Wooing politicians like Gov. Charlie Crist and U.S. Sen. John McCain was a key to the success of his $1.4 billion Ponzi scheme, convicted fraudster Scott Rothstein testified Wednesday in federal court.In a wide-ranging discussion of how he built the scheme and how it imploded in October 2009 that came during his testimony in the trial of lawyer Christina Kitterman, Rothstein was both confident and contrite.