WAPO: 2014 Senate races may be a referendum on Obama; if so, Democrats should worry.

If the 2014 election is a referendum on President Obama, Democrats are in deep trouble.

That’s according to a new state-by-state study of Obama’s job-approval ratings released by Gallup that puts his disapproval rating at over 50 percent in 10 of the 21 states where Democrats are defending Senate seats this fall. In many of those states, Republicans have recruited strong candidates and are preparing to spend big bucks to win the six seats they need to regain the majority.

Obama is deeply unpopular — with a disapproval rating higher than 55 percent — in five states: West Virginia (67.3 percent disapproval), Montana (60.9 percent), South Dakota (59.3 percent), Arkansas (57 percent) and Alaska (55.4 percent).

Beyond those five seats, there is a second tier of states where the president’s disapproval rating stands somewhere between 50 percent and 55 percent, including: Iowa (50.1 percent disapproval), New Hampshire (50.2 percent), North Carolina (50.4 percent), Colorado (51.2 percent) and Louisiana (53.9 percent).

There’s a good chance that second tier will get bigger between now and November.