Both candidates for Indiana's U.S. Senate seat agree that Capitol Hill is dominated by partisan gridlock – but they differ on if and how Congress can solve the problem, even as they compete for the same undecided voters. U.S. Rep. Joe Donnelly, D-Granger, has preached a message of centrism and bipartisanship while relentlessly painting Republican state Treasurer Richard Mourdock as an extreme, right-wing ideologue.