Cordray, Obama's appointee as federal consumer watchdog, faces Republican Attorney General Mike DeWine in one of the season's most closely watched governor's races.
"You can't just get anxious; you can't just mutter to yourself while you're watching TV; you can't put your head in the sand; you can't just boo; you gotta vote", Obama told the hundreds of supporters gathered inside a gymnasium at the East Professional Center at East 79th Street and Superior Avenue.
"Instead of being a check or balance on this kind of behavior, what you're seeing are Republicans in Congress who are bending over backwards to try to shield and deflect oversight of this behavior from scrutiny and accountability and consequences", Obama said at the rally in Cleveland.
Donald Trump Jr., the president's son, was in the state Thursday to raise money for DeWine and Republican U.S. Rep. Jim Renacci, who is seeking to unseat Brown in the Senate.
With the midterm elections fast approaching, Obama has returned to the campaign trail to help Democrats capture the 23 seats they need to regain control of the U.S. House, as well as backing up-and-coming candidates in races important for redistricting after the 2020 Census.
"When President Obama said that he has been to '57 States, ' very little mention in Fake News Media", Trump tweeted on Friday.
Cordray formerly worked for the Obama administration as director of the Consumer Financial Protection Bureau.
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A surge is likely along portions of the SC coast. "Our house is on high ground so we're not anxious about the flooding", he said. As the storm sat along the edge of the Atlantic, some stretches along the coastal Carolinas received close to 20 inches of rain.
Obama drew a contrast between Cordray's polite - some say boring - style and the president's.
"Some of those fights are not over, not by a long shot", Cordray said of the continued Republican efforts to chip away at the ACA, Obama's signature policy achievement, "It's just wrong, and we're not going to let it happen".
That speech marked a dramatic course change for the former president, who has largely stayed out of politics since the 2016 election, and vaulted him back in the national political fray as a key figure leading up to the first major election since Trump's inauguration. Republican Ohio Gov. John Kasich is term-limited.
GMMB was the lead ad agency for Obama's successful presidential bids.
Obama has been trying to make the case that the country has reached a pivotal point, exhorting Democrats and independents to vote in the November elections to reject the policies and behavior of Trump and his Republican allies.
Obama acknowledged the mistake after, saying, "I understand I said there were 57 states today".
Republicans are also seeking to use the former president's visit as a reminder of Cordray's tenure at the consumer watchdog agency that became mired in controversy a year ago when his retirement sparked a legal battle over who would replace him.