Keeping the White House in Democratic hands, no matter who became the Republican nominee, has always been an important goal for Obama.
But the president has long shown a personal disdain for Trump, dating back to when the business mogul became a leader of the “birther” movement that questioned whether Obama was born in the United States.
Obama has repeatedly said Trump could damage the country’s standing abroad while attempting to roll back his accomplishments at home.
The president could face challenges in getting his message to break through against Trump, however, as the businessman has proved masterful at commanding media attention.
The president is still confronting a months-long dilemma about tipping the scales on the Democratic side.