The national polls paint a grim portrait for the Donald Trump campaign. The current Real Clear Politics average of the two-way polls shows Hillary Clinton with a commanding 6.8 percent lead. While there is still plenty of time left in the campaign, it is difficult to overcome such a large deficit after the parties have already held their conventions. This problem is worsened by the fact that the undisciplined Trump seems to lack the wherewithal to right his wobbly ship.
In 2012, Mitt Romney ran relatively close to Barack Obama in the national polls. The final Real Clear Politics average had Obama up by less than one percent, and Romney led in the average for most of the final month of the campaign. There was a notable divergence between the state and national polls that cycle, with the state polls showing Obama in much better shape. The latter turned out to be right, as Obama won a comfortable victory.
What are the state polls showing this cycle?
Over the course of August to date, there has been a decent amount of polling data from red, blue, and purple states. Overall, reputable pollsters have conducted surveys in 14 states, and when we factor those into our analysis, an already bleak outlook for Trump grows darker still. Combined, they show Hillary Clinton on track to win the largest Electoral College victory since 1988.
To illustrate this, I broke the states into three categories: those that have voted Republican and Democratic at least once in the last 16 years; those that have voted only for Democrats; and those that have voted only for Republicans. As a way to gauge Trump's standing, I've used Romney's margin of victory or defeat from 2012 for a baseline. Let's see how Trump stacks up.

The traditional swing states have received the most attention from pollsters, and on balance they show Trump running about 3.5 points behind Romney, which is roughly consistent with a 7-point nationwide defeat (about the magnitude of McCain's loss in 2008). Note that Trump is doing relatively well in Iowa and Ohio, two swing states where the white working class is more prominent. It is not hard to imagine Trump beating Romney's margins in places like Dubuque and Youngstown. Meanwhile, in Colorado and Virginia—two states with much more racial and ethnic diversity—he is running far behind.

The historically blue states show a near-identical portrait, with Trump running solidly behind Romney. The Trump Team continues to talk about Pennsylvania as if it is in play—at the moment, it clearly is not.
The red states are where Trump is really struggling.

This is a substantial underperformance by the Republican nominee. Clinton looks to have corralled much of the Democratic vote in these states, but a good chunk of Republicans are holding out on Trump.
How does all of this factor into the Electoral College? If these numbers hold, all of the purple states would easily fall into Clinton's column. Similarly, the blue states would remain solidly blue. Moreover, Trump would shed several states that have historically been reliably Republican. If he underperforms Romney by 10 points in red states on Election Day, this is what the Electoral College map would look like.

This is not a prediction of what will happen in November, but a projection based upon the current polling. Importantly, it assumes a uniform swing among the red states—that, since Trump is underperforming by an average of 10 points in the states that have been polled, he is doing the same in states that haven't been polled. This is probably not true—there will likely be variation around the average. It also assumes that Trump cannot bring wayward Republicans home. If he does, his margins in the red states will improve.
The point of this exercise is to demonstrate the scope of defeat that Trump is facing. It is incredible. Currently, these numbers point to the largest electoral college landslide since George H.W. Bush's victory in 1988—which has long been seen as impossible in this age of polarized party politics. Maybe these numbers hold, maybe they don't. The point is that Trump is struggling mightily—in all sorts of places the GOP usually takes for granted.
Republicans would do well to consider ditching their efforts to rescue this erratic and undisciplined nominee, and begin focusing on minimizing their losses in the House and Senate. If these margins hold, the only chance the GOP will have to retain either chamber of Congress is to convince a large block of voters to split their tickets. That is no little feat in this age of increasing straight-party voting—so Republicans need to begin making the argument for divided government sooner rather than later.
They should also be ready for problems in surprising states and districts. With numbers like these, Roy Blount is going to struggle to hold his Missouri seat, as will John McCain in Arizona. A whole range of House seats might end up being lost that, at this moment, nobody is really considering. Congressional elections can break late—and if a party is not ready, it can be caught flat-footed.