NEW YORK — Joseph P. Kennedy III, a 31-year-old Massachusetts prosecutor, will run for Congress this year in a bid to resurrect the dynasty of America's most famous political family, reports said Thursday. Kennedy is in the final stages of preparing a Congressional run, with hopes to succeed retiring Democratic Representative Barney Frank, the Boston Globe and Rhode Island Public Radio reported, quoting family and Democratic sources. Should Kennedy win a seat in the House of Representatives, his family would return to national politics for the first time since Patrick Kennedy -- son of the clan's late patriarch Edward Kennedy...