LAS VEGAS (AP) — Democratic Chairman Tom Perez is urging party unity in the fight against what he calls the most dangerous president in history and a Republican culture of corruption. Perez is leading the first Democratic National Committee gathering since his contentious election as party chairman in February. The former Obama administration Cabinet member is trying to smooth over continuing divisions between grassroots activists who backed Bernie Sanders in the 2016 presidential primary and establishment party leaders who want to move on after Hillary Clinton's general election loss to President Donald Trump.