However, Republicans have until Feb. 7 to file a candidate.
Ohio Gov. John Kasich, who is term-limited, apparently is not interested, according to his aide John Weaver.
RELATED: Mandel announces run for Senate
However former Ohio Republican Party Chair Matt Borges posted on Twitter “#draftKasich.”
Secretary of State Jon Husted also confirms that he is not interested. He is running in the governor race with Attorney General Mike DeWine.
A senior Ohio Republican official who spoke on condition of anonymity said Republicans are likely to turn to two candidates currently running for governor - Lt. Gov. Mary Taylor or U.S. Rep Jim Renacci of Wadsworth.
The same official said there "already are efforts to help clear the gubernatorial primary by encourging Mary and Jim to enter the Senate race."
Renacci says it’s not on his mind for now.
“I haven’t even thought about it,” he told the Newark Advocate newspaper.
Mandel issued a statement to his supporters on Friday, saying in part:
“We recently learned that my wife has a health issue that will require my time, attention and presence. In other words, I need to be there. Understanding and dealing with this health issue is more important to me than any political campaign.
For as long as that takes, whether it is months or years, it is important that I heed my dad’s advice and be there for my wife and our kids.”
Josh and Ilana Mandel have three young children.
Brown issued the following statement after Mandel’s announcement:
“At this time, we wish Josh, Ilana and their family the best of health. We hope for Ilana's full and speedy recovery,” Brown said.
Ohio Republican Party Chair Jane Timken said Mandel made “an honorable decision.”
"While we are saddened to see him leave the race, we understand, and offer our thoughts and prayers to his family,” she said.
Here’s Mandel’s full statement:
Over a year ago, I launched a campaign for US Senate to make our state and country a better place for my children and yours. Since then, we've built a campaign that has us on a path to defeating Sherrod Brown this November. We've led him in every public poll and we've been the top fundraising Republican challenger in the country.
That being said, I was raised to believe that family always comes first. I still remember the first two words of advice my father gave me when Ilana and I had our first child: "Be there." These were the same two words his father told him when I was born.
We recently learned that my wife has a health issue that will require my time, attention and presence. In other words, I need to be there.
Understanding and dealing with this health issue is more important to me than any political campaign. For as long as that takes, whether it is months or years, it is important that I heed my dad's advice and be there for my wife and our kids.
After recent discussions with our family and healthcare professionals, it has become clear to us that it's no longer possible for me to be away from home and on the campaign trail for the time needed to run a US Senate race.
Therefore, I'm writing today to let you know that I am ending my campaign for US Senate in order to be there for my wife and our three children. This was a difficult decision for us, but it's the right one.
While unexpected, I accept that this change of course is what God has in store for our family at this time. As we read in the Book of Proverbs, "Many are the plans in a person's heart, but it's God's purpose that prevails."
The issues facing our country are profound and I believe we had a voice and perspective better than the current one in the office. At the same time, I think it's important to acknowledge the respect I have for Senator Brown for having the passion to advocate for his beliefs and, as Teddy Roosevelt once aptly said, the courage to be "The Man in the Arena."
I will continue to serve out the remainder of my term as State Treasurer and hope to have the opportunity to serve my state and country again in the future. But in the meantime, I must put my family first. I'm grateful for your understanding.
This story is developing. Check back for more details.
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