Gov. JB Pritzker said in a statement that he "wishes the President and First Lady a speedy recovery."
U.S. Sen. Dick Durbin echoed Pritzker in a tweet, saying "Wishing the President and First Lady a speedy recovery from this dangerous coronavirus."
Wishing the President and First Lady a speedy recovery from this dangerous coronavirus. https://t.co/WfRYGzKW0q— Senator Dick Durbin (@SenatorDurbin) October 2, 2020
U.S. Sen. Tammy Duckworth also wished the pair a full recovery in a tweet.
Chicago Mayor Lori Lightfoot joined in, saying in a statement she "wishes the President and First Lady a speedy recovery from COVID-19. Let this be a reminder to us all that COVID-19 is real, remains present, and powerful. Please wear a mask."
Voters in the suburbs and the city had mixed reactions.
"I'm not entirely surprised with the way coronavirus has been spreading," said Maggie Durkin, who was voting early in DuPage County. "I figured at some point in time someone was going to get it with the campaigning and the debates."
"I'm not concerned with it," said Terry Zaio, also voting in DuPage County. "He's a healthy person to begin with."
"I don't want him to be sick but I think it's gonna have a big effect on how things go from here," said Kathleen Weinberg, who voted early in Chicgao.
Chicago Alderman Raymond Lopez of the 15th Ward said in a tweet that he's praying for Trump and the first lady.
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"Hoping this brings some newfound humility & respect for the millions of Americans confronting this virus w/o the resources needed to survive," Lopez said.
I wouldn’t wish #covid19 on anyone. It’s effects are long term if it doesn’t kill you. I pray for @realDonaldTrump & @FLOTUS safe recovery, hoping this brings some newfound humility & respect for the millions of Americans confronting this virus w/o the resources needed to survive— Ald. Raymond Lopez (@RLopez15thWard) October 2, 2020
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U.S. Rep. Darin LaHood, R-Peoria, said in a tweet that his prayers are with the Trumps.
U.S. Rep. Adam Kinzinger, R-Channahon, tweeted his wishes for "a swift & safe recovery."
Praying for our President & First Lady and wishing them both a swift & safe recovery. https://t.co/CdFyWc19QX— Adam Kinzinger (@RepKinzinger) October 2, 2020
Chicago activist Father Michael Pfleger said those rejoicing at the Trumps' testing positive is wrong, but he prays "that this will allow him to tell us to take this seriously."
As i see Social Media, some are rejoicing at the President testing positive, this is wrong. I am a fierce but as my mentor Dr. King said, we hate the sin not the sinner. I pray for his Healing and strength, and pray that this will allow him to tell us to take this seriously— Fr. Michael Pfleger (@MichaelPfleger) October 2, 2020
Wisconsin Gov. Tony Evers sent his best wishes to the president and first lady in a tweet.
Kathy and I are sending our best wishes to President Trump and First Lady Melania Trump in their recovery.— Governor Tony Evers (@GovEvers) October 2, 2020
Former Illinois Gov. Rod Blagojevich said in a Facebook post that he and Patti "will never forget President Trump's kindness to us."
The president said he and the first lady are self-isolating; he is expected to continue carrying out his duties while recovering.
"Tonight, @FLOTUS and I tested positive for COVID-19. We will begin our quarantine and recovery process immediately," Trump tweeted. "We will get through this TOGETHER!"
Tonight, @FLOTUS and I tested positive for COVID-19. We will begin our quarantine and recovery process immediately. We will get through this TOGETHER!— Donald J. Trump (@realDonaldTrump) October 2, 2020
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Vice President Mike Pence and Second Lady Karen Pence tested negative later Friday morning.
Democratic presidential candidate Joe Biden also tested negative later Friday.
As early Chicago voters gathered outside the Loop Super Site Friday morning, some said the president's diagnosis did not come as a shock.
"It's a reality check for him and others who were going around not wearing masks and not protecting themselves and others against the pandemic," voter Dana Pointer said.
The president's age has some voter's worried. Trump is 74.
"I don't want him to be sick, but I think it's gonna have a big effect on how things go from here," early voter Kathleen Weinberg said. "He's a high risk person as an older person. He could not do well."
The Associated Press contributed to this report.