1. Republicans are antipathetic to government in general
Republicans are generally less enthusiastic about government than Democrats, which probably won't surprise you. On a wide range of issues, Republicans think the government should have a smaller role than Democrats, from access to health care (in which only a third of Republicans think the government should be involved) to strengthening the economy.
In general, Republicans think the government does too much.
What's more, Republicans are much more likely than Democrats to think that government is too big — and the gap is widening. In 2004, Republicans were about 25 percentage points more likely to say government was too big. Now, the split is nearly 50 points.
2. Trust in government is partisan
One of the findings from Pew is that trust in government — which near a record low — is subject to partisanship. When a Democrat is in the White House, liberals have more trust in government; when it's a Republican, conservatives do. Below, the gap between liberals and conservatives since 1992.
In other words, at the tail end of the second Obama term, conservative trust in government is much lower than it might otherwise be.
3. Republicans feel like they've been losing political fights
Most Americans think that their political side has been losing more than winning. Two-thirds of people feel that way. But conservatives feel that way much more strongly. Eighty-one percent of conservatives think that they're losing, versus 44 percent of liberals — the only group among which a plurality thinks that they're winning.
Clearly, there's overlap between a lot of these attitudes. Having President Obama in the White House will naturally make conservatives less trusting of what the government is doing, and his reelection will naturally make some people feel as though they're losing.
But it's likely that the sense of losing among Republicans stems in part from their lower enthusiasm for compromise. Pew's survey confirms that Republicans are still more likely to prefer politicians that stick to their positions than ones who make compromises. Republicans prefer sticking to positions 21 points more than they back compromise; Democrats are about the mirror opposite.
4. Republican primary voters overlap with the angriest groups
That sense of losing also makes people feel more angry about the government. A quarter of those who feel like they lose more than win were angry at government. Only 9 percent of that group was content with the government.
Anger at government was also higher among those who see immigrants as a burden to the country and those who are less optimistic about our future. The Pew survey took place from the end of August to early October of this year, a period during which the leading Republican candidate espoused both a strong anti-illegal immigrant position and a pessimism about the current position of the country. There's a bit of a chicken-egg situation in this: e.g., Did enthusiasm for Trump make people more likely to view illegal immigration negatively? But there are clear parallels.
There's an operating theory of the Trump dominance, nicely articulated by 538, that it's driven in part by the fact that the Republicans most engaged in the primary process right now are also the most politically active. Indifferent voters will start paying attention closer to Election Day, and they'll weigh in on behalf of the establishment more strongly.
Pew's research finds that the most politically engaged Republicans are also those most angry at the government and the most likely to see the government as wasteful and inefficient. Those more-engaged voters are also, definitionally, those who've been paying more attention to the primary.
5. Republicans are more likely to think normal people could do a better job than politicians
In 1996, a fifth of Republicans viewed government as the "enemy." In 2015, more than a third do — while the number among Democrats remained the same.
Republicans are (perhaps unsurprisingly in light of that) more likely to say that ordinary people could do a better job than politicians at solving problems.
Pew weighed favorability for leading Republicans against how angry the voter was. The candidate least popular among angry voters? Jeb Bush, almost certainly the most heavily establishment candidate in the race. Interestingly, Marco Rubio — not exactly an outsider — sees strong favorability from angry voters. Rubio's campaign has hoped to be able to straddle the line between establishment and outsider acceptability, which it seems as though he's managing so far.
At least in 2015, before the less-engaged voters start paying attention, that's perhaps about as good as a sitting U.S. senator could do. The Pew data suggests that this is about an ideal moment for a candidate who can articulate a case to the Republican base that they oppose government and, even better, were never a part of it.
But: We sort of knew that.