CINCINNATI — Ohio Sen. Rob Portman said Monday that he won’t seek reelection to a third term in 2022, expressing dismay with the deep partisanship and dysfunction in American politics. The career establishment Republican with a reputation for bipartisanship cited a political climate that has made it “harder to break through the partisan gridlock and make progress.” “Our country is very polarized,” Portman said, adding that former President Donald Trump did not help with the polarization.