Um, they started campaigning against repealing what he had done because THEY WERE VOTED INTO OFFICE TO DO SO. Do you think it's a magical coincidence that, following 2 years of President Obama, a Pelosi-led House and a Reid-led Senate (filibuster-proof majority!), 64 of those House D's lost their seats, and about 40 went to Tea Party/Freedom Caucus types? And they've added 5 seats since to that? And that the Senate D's have lost 16 seats since 2010?
I'm someone who wants smaller government, less military intervention in nation-building, diplomacy from strength, people to follow the laws (including but not limited to immigration), the majority of Pell Grants and other Federal Grants to go to student in STEM programs, Social Security to pay for Social Security (whether that means increase the tax % or increase retirement age is a debate we can have), Medicare/Caid to pay for Medicare/Caid (same caveats), comprehensive health care reform (not just lining insurance company pockets), intelligent alternative energy sources, and for religion to be out of government control. Many of those voted in over the last 5 years believe many/most of those things, and the President doesn't. I, as one voter, don't want to see the President accomplish almost anything on his agenda, and want a repeal of some of the stuff he and those already voted out have already accomplished. And many of the constituents of people voted in agree.
I get that that doesn't play well in Oregon.