WASHINGTON (Reuters) -U.S. Representative Jamie Raskin, a leading liberal voice in Congress, urged his fellow Democrats on Thursday to avoid an "obvious political trap" and vote for a Republican resolution honoring the assassinated conservative activist Charlie Kirk. Kirk's killing last week while he addressed a college audience in Utah has sparked a political furor across the U.S., with President Donald Trump and his allies vowing a crackdown on left-leaning groups that they portray as bent on undermining national unity. There is no evidence the 22-year-old Utah man who killed Kirk with a single rifle shot had organized outside help in plotting his attack.