Paul Manafort resigned as chairman of Donald Trump's U.S. presidential campaign on Friday, no longer enjoying the full confidence of a Republican candidate who is trying to boost his flagging White House bid. Trump said in a statement he had accepted Manafort's resignation, but did not offer an explanation for the departure. It came in a week when Trump has already reshuffled top campaign leaders, effectively demoting Manafort, and has tried to be more disciplined and on message as he seeks to reset his campaign against Democratic rival Hillary Clinton for the Nov. 8 election. A person close to the campaign said Trump had been unhappy with Manafort for a variety of reasons. Trump's son, Eric Trump, said unflattering headlines about Manafort were taking a toll.