Trump gave a full-throated endorsement to state Sen.
He questioned the idea that the party that controls the White House suffers in the midterm elections.
Trump also brought to the stage Ohio Representative Jim Jordan, "a tough cookie". Both Kasich and Trump have endorsed Balderson.
After calling MSNBC and CNN a "fake news group of people", Trump said "here's the good news".
Hundreds of people are slowly making their way into an OH high school ahead of a rally headlined by President Donald Trump.
Trump is set to hold a rally in OH this weekend for congressional candidate in the state, Troy Balderson.
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Trump predicted a "tremendous victory" for Balderson, who polls say is in a dead heat in his race against Democrat Danny O'Connor, the Franklin County recorder.
"It's likely in the end that Balderson should be able to win narrowly", he said.
"Suburban women in particular here are the ones that are really turned off", Kasich said.
Democrats have "a weak candidate because there's no message", he declared.
Here in CT, of course, that latter term is said in revulsion by GOP leadership to describe funds that are used to attract industry to this state in competition against primarily Republican-ruled states that also dangle financial incentives before companies to induce them to locate there.
The Ohio rally was Trump's third of the week and he has pledged to accelerate his pace further as the midterms approach.
The congressional seat has been vacant since January, when nine-term congressman Patrick Tiberi resigned. The attack on James, who has been critical of Trump, came just as the National Basketball Association superstar opened up a school for underprivileged children.