Barack Obama vs. Donald Trump: 'Stop Whining' And 5 Other Times The President Criticized The GOP Nominee

Part of President Barack Obama's endorsement and support of Democratic nominee Hillary Clinton means the commander in chief hitting the campaign trail. And part of stumping for Clinton has meant weighing in on Donald Trump. 

"Stop whining and go try to make his case," was Obama's suggestion for Trump when asked about the GOP nominee's warnings of voter fraud during a press conference in the White House Rose Garden on Tuesday with Italian Prime Minster Matteo Renzi.