This question is a great example of data that deserves more context. For example, here's what happens when you compare the results of that question with three other questions asked by Monmouth:
- Do you think Trump is keeping his taxes private because of the audit process or because there is something in those returns he doesn't want the public to know?
- Is your general impression of Trump favorable or unfavorable?
- Who do you plan to support in November?
Responses to those questions, when broken down by party, look ... awfully similar.
Eighty percent of Democrats think that it's very or somewhat important to release taxes — and 82 percent think Trump is hiding something, and 84 percent view him unfavorably, and 85 percent pick Clinton in a head-to-head match-up.
The numbers for Republicans and independents are a bit more mixed. Fifty-four percent of Republicans think that releasing tax returns isn't important — while 47 percent take him at his word that an audit is the cause. Trump gets only 78 percent of support from Republicans, which is likely why he continues to trail Clinton overall (by 7 points). We'll come back to that.
Independents are more skeptical of Trump — and Clinton. Asked whether the overlap between Clinton's work at the State Department and her family's foundation was nothing out of the ordinary or a sign of special treatment, more than half of Democrats said it was nothing out of the ordinary, while 58 percent of independents said it indicated special treatment. (And 80 percent of Republicans said the same.)
In other words, Republicans view Trump more generously (including on tax returns) and Democrats view Clinton more generously ... and independents dislike them both. That's made obvious in Monmouth's delineation of how voters feel about the two candidates: A plurality dislike them both.
If you don't like a candidate, you'll offer skepticism about their behavior. That's the trend in that first set of graphs, not that Americans are suddenly curious about taxable income figures.
The implications here are important. Adding Monmouth's new head-to-head numbers into the RealClearPolitics average, you can see that Clinton continues to hold a fairly steady lead over Trump even as his numbers recover a bit.
With the election drawing closer, Trump continues to be mired in the lower 40s in polling, with Clinton about 6 points ahead of him. Trump's failure to consolidate support from Republicans has been a constant since the conventions, and so far nothing his campaign has done has changed that. So how does he, once and for all, get past 45 percent in the polls — much less past Clinton?
Trump's campaign manager, Kellyanne Conway, recognizes that part of the problem is that people like to talk about the things that Trump does instead of the positions he advocates. (This is in part because the positions he advocates are not exactly set in stone.) She has called for the campaign to focus on policy (even as Trump's signature policy stance on immigration seems to be in flux). But as Trump himself noted a year ago, voters don't really care that much about policy proposals, any more than they are interested in poring over tax returns. Whether or not Trump releases his tax returns, it's unlikely to change much in the race because so many voters have already made up their minds about their distaste for both candidates.
In other words, the tax poll numbers don't really tell us anything about how Americans feel about taxes. But they tell us a lot about how people feel about the candidates, which is why, after 440 days of campaigning, Trump is trailing the way that he is.