Former President Obama tells allies Biden needs to seriously ...

CHICAGO (WLS) -- President Joe Biden's political future is even more uncertain Thursday night.

He's off the campaign trail following his third COVID diagnosis.

And there is word that former President Barack Obama is now weighing in.

It's being reported that Obama has told allies that Biden needs to seriously consider the viability of his candidacy.

For now, the Biden campaign insists the president will be back on the campaign trail as soon as he can.

Vice President Kamala Harris was at a rally Thursday, blasting J.D. Vance.

The camera phones were up, as the spotlight continues to focus on Harris, while Biden gets more pressure to drop out.

At a campaign stop in Fayetteville, North Carolina, the vice president aggressively responded to Republican vice presidential candidate J.D. Vance's speech Wednesday night at the Republican Convention.

She doubted Vance's claim of unity.

"You cannot claim you stand for unity, if you are pushing an agenda that deprives whole groups of Americans of basic freedoms, opportunity and dignity," Harris said.

Harris is doing the talking Thursday, as President Biden is recovering from COVID, at his home in Rehoboth Beach Delaware.

The White House released a letter from the president's physician.

Dr. Kevin O'Conner said Biden is experiencing mild symptoms.

But, it's being reported former President Obama has told allies that Biden's path to victory has greatly diminished.

"I think all of this is driven by the fact that donations are drying up; polling numbers are going in the wrong direction," said U.S. Rep. Mike Quigley, a Democrat from Illinois' 5th District.

Chicago-area Congressman Mike Quigley was one of the first in Congress to call for the president to drop out of the race.

He said the president is down in the polls in over 10 swing states, which can have a big effect on down-ballot races.

Quigley said, up until recently, he did not believe Biden was receiving accurate information from his staff about the polls.

"I believe that the president was cloistered. I honestly wouldn't be surprised if the campaign disregarded all the bad news and frankly misled the president," Quigley said.

White House officials say, as soon as the president recovers, he will be back on the campaign trail.

Illinois Gov. JB Pritzker, who has been serving as a surrogate for Biden, will also be on the trail.

"I went to Ohio and Indiana last weekend to campaign for President Biden and Vice President Harris, and I'm going to continue to do that. He apparently is going to be our nominee," Pritzker said.

But more top Democrats are worried a Biden loss could also mean a Republican sweep in the House and Senate.

The Associated Press contributed to this report.