WASHINGTON (AP) -- A political group backed by billionaires Charles and David Koch is pumping another $2.2 million into television and digital ads in Ohio's Senate race.
The latest ad wave brings the investment of the Kochs' well-funded network to about $7.7 million on paid media in the matchup between incumbent Republican Sen. Rob Portman and Democratic former Gov. Ted Strickland. Koch groups including Americans for Prosperity also have been knocking on doors and making phone calls to voters to boost Portman support.
The anti-Strickland ads focus on taxes and fees he raised while in office.
The Ohio spending comes as the billionaires have distanced themselves from the presidential race and presumptive GOP nominee Donald Trump and focused, at least for now, solely on protecting the Republican-led Senate and House.