Philadelphia: Former President Barack Obama returned to the campaign trail on Wednesday, launching a blistering attack on Donald Trump with less than two weeks to go before the Republican president’s Election Day face-off with Democratic nominee Joe Biden.

Obama said Trump was not interested in the job and was using the presidency as a reality show to get attention.

“He hasn’t shown any interest in doing the work or helping anybody but himself,” Obama said.

“We’ve got to turn out like never before,” he said. “We cannot leave any doubt in this election.”

Obama, who governed for two terms and remains one of the most popular figures in the Democratic Party, blasted Trump for his handling of the coronavirus pandemic, noting that the president himself had fallen victim to the virus.

“Donald Trump isn’t suddenly going to protect all of us,” he said. “He can’t even take the basic steps to protect himself.”

Meanwhile, Trump trained most of his fire during his rally in Gastonia on Wednesday evening on his current Democratic challenger for the White House.

He said the choice for voters was between a "Trump super-recovery" or a "Biden steep depression".

Biden has been off the campaign trail all week preparing for the final presidential debate on Thursday night in Nashville, Tennessee, while Trump barnstorms the battleground states.

"There was nobody that campaigned harder for crooked Hillary Clinton than Obama, right?" Trump told rally-goers, who booed at the mention of his old adversaries' names. "He was all over the place."

The President added: "I think the only one more unhappy than crooked Hillary that night was Barack Hussein Obama."

Americans are voting early at a record pace this year, with 42 million ballots cast both via mail and in person ahead of the Nov. 3 election on concerns about the coronavirus and to make sure their votes are counted.