What is Trump’s approval rating?

President Trump’s current approval rating isn’t very important right now (though it may be to President Trump), but all of us would like to know what that rating is. In its latest survey, Rasmussen puts the approval number at 51 percent, with 49 percent disapproving.

This is Trump’s best showing in a Rasmussen poll since early March. However, Trump’s approval rating has hovered at close to 50 percent for the past two weeks.

Rasmussen’s results vary significantly from what other polls say. They have Trump under water by margins varying from 6 to 16 points.

Obviously, Rasmussen is an outlier. But why? Is it a fluke; is it the product of methodology; or is raw bias operating in his poll or in others?

One pollster told me that Rasmussen uses a sample whose mix of Democrats and Republicans mirrors the split on Election Day. In most other polls, he says, the sample consists of a higher proportion of Democrats than in Rasmussen’s.

This doesn’t mean that anyone is placing a thumb on the scale. It may be that six months after the election, many more people consider themselves Democrats than did before Trump won the presidency. This would be true if, for example, Republican “leaners” have moved away from the party or if independents have become Democratic “leaners.” One might expect such developments if Trump’s presidency is unpopular.

Nate Silver of FiveThirtyEight has cited two methodological differences that can explain the polling disparities. They are (1) the sampling of all adults vs. registered voters vs. likely voters and (2) the use of live-caller vs. automatic script vs. online polls.

Trump tends to do best if a poll samples likely voters and if the poll is conducted online or by automatic script. I have no opinion on calling vs. online polling. I think that sampling likely voters provides the best sense of how the 2018 election will turn out. This is the most important question many of us are thinking about when we look at presidential approval ratings (though, again, such ratings aren’t very meaningful for this, or any other, purpose right now).

FiveThiryEight looks at recent polls. Purporting to take into account each poll’s “quality, recency, sample size and partisan lean,” it concludes that 41.8 approve of the president’s job performance while 52.7 disapprove. For what little it’s worth, I think Trump may be faring a bit better than that.

But even if FiveThirtyEight has it right, America’s view of Trump is probably more favorable than when it elected him president.