President Barack Obama ’s advisers are lining up against the proposed Keystone XL oil pipeline. Top Democratic donors oppose the project. And Obama himself dismisses claims that it will create many jobs. Yet there’s still one big obstacle to the president saying no to Keystone: election-year politics. If Obama rejects the pipeline, it might sink Democratic candidates in states with big energy industries, such as Louisiana and Alaska . That could cost Democrats control of the Senate — a risk that’s likely to weigh heavily on any decision the president makes, to approve the pipeline, reject it or wait until […]