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It's hard to know how much of the mania around Donald Trump's candidacy stems from Trump himself and how much that energy is what spurred people to back him. If you ask a fan of Donald Trump today how important it is to build a wall on the southern border, he or she would almost certainly say that it's very important. But is that because such people strongly believed in the need for a wall and therefore are voting for Trump, or is it because Trump strongly advocates a wall and so his fans are echoing the view of their preferred candidate? It can be hard to suss out which came first. One could analogize to the birth cycle of a domesticated farm avian.

Put another way: If we stick a thermometer in a big pool of Trump voters, we can tell how warmed up they are, but not necessarily why. That's important context for a new survey from Quinnipiac University, which does exactly that. And Trump voters are boiling.

Nine out of 10 Trump voters, for example, say they strongly or somewhat agree with the statement that "my beliefs and values are under attack in America these days." Seventy-eight percent agree that they're falling further behind economically. Eighty percent agree that the government "has gone too far in assisting minority groups."

But Trump voters aren't entirely alone. Eighty-five percent of all Republicans think that their beliefs and values are under attack. Two-thirds say they're falling behind economically. There are wide splits between the candidates -- and wider splits between the parties.

Consider the question of whether or not America has lost its identity. We can compare the two extremes, those who say they strongly agree that America has lost its identity with those who strongly disagree with that idea. On net, Trump voters are much more likely to agree with that statement than are supporters of any other candidate. Democrats largely disagree with the statement -- but supporters of Bernie Sanders are much less likely to disagree.

The difference between backers of the two Democratic candidates is starkly demonstrated in Quinnipiac's question about economic security.

Economic security is a centerpiece of Sanders's campaign argument, but it's still remarkable that more than half of his supporters agree with the statement, while more than half of Hillary Clinton's don't.

The biggest gulf between the two parties in Quinnipiac's polling was on the extent to which assistance for minority groups has or hasn't gone too far. The split among Trump voters is as wide as the split on the question of America's lost identity.

In some ways, Sanders supporters's frustration with the way the system works mirrors members of the party that wants to re-take the White House. On the need for radical change, the split between strong agreement and disagreement among Sanders supporters looks like attitudes from Republicans.

Supporters of Clinton, the only viable establishment candidate still running, disagree.

Sanders and Trump fans are also more likely to see their candidates's campaigns as political movements, rather than campaigns. But, then, supporters of every candidate like to feel that way on net.

Quinnipiac also asked people how they felt about the balance between compromise and leadership. Unsurprisingly, fans of Trump were much more likely to say that true leaders don't worry about what others have to say.

And, to put a fine point on it:

Did Trump supporters spend most of the first half of 2015 pining for a guy who'd ignore political correctness in his campaign, or did they simply embrace the guy that's used precisely that strategy?

In this case, it's probably a little bit of both.