First, there are some differences between the 2012 race and the WaPo polling, which I have highlighted in yellow. Not all of these differences are Dems vs GOP, but rather, differences is amount. For example, Rhode Island has no surprises in their choice--Democrats. However, in 2012 Obama won Rhode Island by 27 points, and currently, Hillary is polling at a 10 point lead over Trump. Similarly, in 2012, Romney won Utah by a whopping 47%, but Trump only has an 11 point lead in this WaPo poll. Earlier polling showed his lead at 20 points.
Third, there are also a few significant differences in today's WaPo results and earlier polling, although only one is a "switch," Ohio--earlier polling gave Clinton an average of a 4 point lead, while today's WaPo results give Trump a 3 point lead. These results would be within the margin of error, so the differences are largely uninteresting, but similarly, unhelpful in predicting a winner, other than to say, "it's likely to be close." Two states, Colorado and Wisconsin, had Clinton with a 10 point lead in earlier polls, but today's results give her only a 2 point lead. The latter results puts it in the margin of error, so could be a significantly tightening rate there.
Just for funzies, let's use the WaPo results as a blueprint, and see what it would produce in terms of an electoral result (neither Texas nor DC were in this poll--for the sake of argument, let's give Texas to Trump, and DC to Clinton--polling averages give Trump an 8 point lead in Texas). First, if we use it "as is," ignoring margin of error, and leaving out Georgia and North Carolina, where polling has a dead heat (0), Clinton gets 325 electoral votes, Trump with 182--a landslide for Clinton. Second, let's only use states where candidates have a 5 point or more lead--That gives Clinton 224, and Trump 158. At the 5-point cutoff, Clinton doesn't garner enough electoral votes to reach the required 270, although, with a 66 point advantage, we still have a reasonably likely Clinton win. In this scenario, she only needs a couple of the states that Obama won in 2012, like Florida+Pennsylvania. Trump's path is far more difficult--he would need to win most of these 11 states. For example, if he lost both Florida and Pennsylvania, he only gets to 265 electoral votes. Or, if we combine a 2012 Obama with with earlier pro-Clinton polling, say, if Trump loses Ohio, Michigan, Wisconsin, and Colorado, Clinton wins. In all, a Trump win is still a statistical possibility, but the path forward for Clinton continues to be far more mathematically obvious.