(CNN) – GOP Sen. Rob Portman defended his party's presumptive presidential nominee Monday from President Barack Obama's "personal" attacks, saying the Democrat was focusing on Mitt Romney because his record falls short.
Portman, speaking in Lebanon, Ohio, was holding an event for Romney roughly two hours ahead of Obama's own campaign speech in nearly Cincinnati.
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"The president said back in 2008 when he was running for office complaining about the Republican campaign, he said, 'When you're out of fresh ideas you turn to stale tactics, to attack your opponent because you don't want to talk about your record.' He said that makes big elections about small things. That's exactly what he's doing right now," Portman, who represents Ohio in the Senate, said Monday.
Romney's campaign has decried the negative tone of the presidential campaign in recent days, including running a television advertisement focusing on television pundits who question Obama's "Hope and Change" slogan from 2008.
The spot, which was released Sunday, came after a series of interviews from Romney in which he said attacks coming from Obama's campaign were "disgusting" and "demeaning."
"It's something which I think the president should take responsibility for and stop," Romney told CNN national political correspondent Jim Acosta.
Portman said Monday the attacks, which have included calls for Romney to release additional income tax return information, were distracting from a failed record.
"He's attacking Mitt Romney on a personal basis. Why? Because he doesn't want to talk about his record," Portman said.
Later Portman said voters weren't served by the type of attacks coming from Obama's campaign.
"We don't need to keep attacking people for success, we don't need the class warfare rhetoric," Portman said.
Portman is widely speculated to be a potential vice-presidential pick for Mitt Romney. Last week Portman said he met with Romney campaign staffers during three meetings while in Boston to headline a couple of fund-raisers for the presumptive Republican presidential nominee.
But Portman, a former congressman and cabinet member in the George W. Bush administration, said the meetings were not at the Romney campaign headquarters, and had nothing to do with the vice-presidential vetting process.
On Monday, he refused to speculate on the vice presidential selection process, and wouldn't say whether or not Romney had yet made up his mind on his running mate.
Portman added he thought "people vote for presidential candidate, not the vice president."
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