In the past, party affiliation was beneficial for presidential candidates when it came to getting elected. Republicans and Democrats may likely have a team favorite: perhaps George H.W. Bush for the GOP or John F. Kennedy for the Democrats. Independents (or non-affiliated voters), on the other hand, are a fickle bunch. Nevertheless, three post-WW II U.S. presidents have been able to transcend party lines and capture the approval of the independent voters of their time, according to data provide...