Sen. Jeff Merkley: Going After The Koch Brothers Stopped The GOP Wave In Oregon WASHINGTON -- From North Carolina to Colorado to Alaska, Democratic senators were swept out of office on Election Day by a GOP wave. Sen. Jeff Merkley (D-Ore.) was one of the few exceptions. At one point a target of national Republicans, Merkley handily defeated his Republican opponent, Monica Wehby, by more than 18 percentage points, despite predictions early on that he could be in danger of losing his seat. Merkley seemed relieved that the campaign was over during an interview with The Huffington Post Wednesday in his office on Capitol Hill, where he reflected on the campaign.