As Democrats try to tie these incumbents to their party's standard-bearer, Republican senators are staying in their home states to campaign instead of making the trip to Cleveland.
Portman has spoken at the past six Republican conventions, but this year, facing a tough re-election race made even more challenging by the ascendence of Donald Trump, he chose to focus attention on his volunteers and embracing this city with charity events.
2016 presidential candidate John Kasich.
Kasich, a rival of Trump's for the Republican nomination, has not endorsed his party's likely standard bearer and has been critical of Trump.
Holt asks what if Trump asked Kasich to speak.
"Kasich is a non-factor at this point in my mind, as far as presidential politics", said John DeFrancisco, a Kasich delegate and deputy leader of the New York State Senate.
It's rare for a governor to skip his party's convention when it's in his home state, but Kasich said earlier this week that he wouldn't show up unless Trump "changes everything that he says".
Law says Trumbull County doubled it's number of GOP registered voters in the primary.
"Compared to Hillary Clinton, Donald Trump looks pretty good, " Chabot said.
Republican incumbent Rob Portman will be working on a Habitat for Humanity house, tackling a nearby kayak course, speaking to Ohio Republicans during a breakfast meeting and others throughout the week and launching ads aimed directly at his Democratic opponent, former Gov. and Congressman Ted Strickland.
"When he was criticizing the judge who has a Mexican background, I found that objectionable, " Chabot said.
Some Trump supporters are livid with Kasich's refusal to back the presumptive Republican nominee.
Portman said he disagreed with the Trump campaign's efforts to scale back language supporting Ukraine in the new GOP platform. However, he is in Cleveland and has been trying to court votes while distancing himself from Trump, Copeland says.
But Manafort insists the number of holdouts has been overstated.
"We're not running presidential races", said Ward Baker, the executive director of the National Republican Senatorial Committee, told Politico.
On Sunday, Rubio, who withdrew from the race in March after a humiliating loss in his own state's primary, was announced as a prime-time speaker, according to the Dallas Morning News.
Still, after the event, Ohioans expressed doubts about Kasich's anti-Trump stance and his plan to avoid the convention.
This isn't the only instance of a Trump surrogate condemning the Republicans who are abstaining from showing up to the convention.
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