Hillary Clinton plans to return to the campaign trail Thursday after being sidelined for the last several days with pneumonia.
A spokesman for the Democratic presidential candidate said Tuesday that details of her schedule would be announced later.
While Clinton continued to recuperate, she got a rousing endorsement from the country's number one Democrat and her former boss, President Barack Obama.
"I am really into electing Hillary Clinton," Obama told cheering supporters at a sun-drenched rally in Philadelphia, a Democratic bastion where Clinton needs a robust voter turnout in the November 8 election against Republican Donald Trump.
"I have seen how smart and savvy and tough she is. I had a front-row seat for four years," Obama said of his onetime political foe who was the country's top diplomat from 2009 to 2013.
Obama mocked Trump, saying he "is not in any way, shape or form fit to represent this county abroad and be our commander in chief."
He belittled Trump's praise for Russian President Vladimir Putin as "a strong leader, because he invades smaller countries, jails his opponents, controls the press and drives his economy into a long recession."
The president added, "I have to do business with Putin. I have to do business with Russia. That's part of foreign policy, but I don't go around saying that's my role model."
Republican presidential candidate Donald Trump gives thumbs-up as he arrives to speak at a campaign a rally in Clive, Iowa, Sept. 13, 2016.
Trump campaigned in the Midwestern state of Iowa, promising to bring back jobs from other countries, where American corporations moved them in search of cheaper labor and bigger profits.
"It's time to embrace a new and prosperous, and I do mean prosperous, America," Trump said.
He later appeared outside Philadelphia, where he unveiled details of his plans for making child care more affordable for American families and working mothers.
WATCH: Trump's running mate Mike Pence on 'deplorables'
He vowed to be "the president of everyone," continuing to attack Clinton for her remark last week that half of Trump's supporters were made up of a "basket of deplorables" because of what she said were their "racist, sexist, homophobic, xenophobic, Islamaphobic" views.
A day later, Clinton said she regretted saying that half of his voters had such views, but otherwise stood by her remark.
The two candidates will square off in the first of three planned presidential debates on September 26, six weeks ahead of the election.
Comparing Polls in General Elections (Source: RealClearPolitics)
The latest U.S. political surveys showed Trump edging closer to Clinton, with RealClearPolitics' average of polls giving Clinton a 2.4 percentage-point advantage, down from about 8 points a month ago.
The weekly NBC News/Survey Monkey poll released Tuesday showed Clinton ahead 48 percent to 44 percent, with Trump 2 percentage points closer than a week ago.