Welcome to Pollapalooza, our weekly polling roundup.

Poll of the week

Since taking office, President Trump has faced an onslaught of controversies — allegations of infidelity and shady connections with Russia, backlashes to family separations at the border and criticism of the government’s hurricane response. His poll numbers, although historically low, have remained relatively steady, giving rise to the idea that nothing can move opinions of Trump. That was never really true. And a drop in Trump’s approval ratings in recent weeks is further evidence of that.

What’s behind the decline in Trump’s approval rating? It’s impossible to pinpoint the exact cause(s), but polls released this week suggest that special counsel Robert Mueller’s investigation into Russia interference in the 2016 election might have a role in it all.

The important thing here is the timing: On Aug. 20, Trump had a net approval rating of -10 percentage points. On Aug. 21, Paul Manafort, former chairman of Trump’s presidential campaign, was found guilty of bank and tax fraud, and Michael Cohen, who used to be Trump’s lawyer, pleaded guilty to federal crimes related to the Trump campaign. Both were implicated as a result of Mueller’s investigation. And it’s really been since then that we’ve seen the movement in Trump’s approval rating (now -14 points), the generic congressional ballot and, notably, views of the Russia investigation itself.

Let’s start with a new CNN poll that found voters, by a 20 percentage point margin, approved of Mueller (50 percent) over Trump (30 percent) when it comes to the handling of the Russia investigation. Mueller’s approval rating has expanded 9 points since CNN asked the same question in June and 3 points since it asked in early August. Trump’s approval rating, on the other hand, has jumped 1 point since June but dropped 4 points since last month.

Here’s what else the CNN poll found:

61 percent of of respondents said the investigation is serious and should be fully investigated. That’s up 6 points since June and 3 points since August. Fewer people (33 percent) than in the previous two polls said the investigation is an effort to discredit Trump.

72 percent said Trump should testify under oath in the investigation if he’s asked, up 4 points since June.

47 percent said Trump should be impeached and removed from office, a 5-point jump since June.

These findings might be easy to dismiss if it was just one poll, but other recent polls suggest a similar trend.

Quinnipiac:

By a margin of 55-32, voters said Mueller is conducting a fair investigation; that’s a 4-point jump from a Quinnipiac poll conducted a month ago.

50 percent said they would disapprove if Trump fired Attorney General Jeff Sessions, who recused himself from the FBI investigation.

YouGov

By a margin of 19 points, Americans said they approved of Mueller’s investigation 49 percent to 30 percent.

39 percent of Americans said they approved of the way Mueller is handling his job. That is a 4-point jump from June.

49 percent said they believe the FBI investigation into Trump is legitimate (while 35 percent said it’s a “witch hunt.”) That’s up 5 points since a June poll.

Mueller’s favorability rating was also up, since June, in three recent polls to ask about it:

Robert Mueller’s favorability rating has improved a bit Pollster June September Change CNN 32% 36% +4 Morning Consult 32 34 +2 YouGov 32 35 +3

That’s not a huge shift, obviously, but combined with all the data mentioned above, the polls are telling a pretty consistent story: It seems that the developments in the Mueller investigation — the Manafort and Cohen news, in particular — have increased public support for the probe. It’s hard to say whether opinions will stick or change in the coming weeks as the Russia investigation continues, but the more support Mueller has, the riskier it will be for the White House if Trump attempts to get in the way of the investigation, say by firing Sessions. Further developments in the investigation could ultimately worsen Republican congressional candidates’ position in the polls too.

Other polling nuggets

Trump approval

Polls this week showed Trump’s approval rating holding steady after its recent decline. His net approval rating currently sits at -13.8 points, according to our tracker. (That’s a 39.9 percent approval rating and a 53.7 percent disapproval rating.) That’s about the same net approval from one week ago, when it stood at -13.7 points; 40.0 percent of Americans approved of Trump’s job performance and 53.7 percent disapproved. At this time last month, that net approval was -10.7 points — 41.8 percent approval, 52.5 percent disapproval.

Generic ballot

According to our tracker of generic congressional ballot polls, Americans currently opt for a hypothetical Democratic House candidate over a hypothetical Republican by a 9.1-point margin (48.8 percent to 39.7 percent). Democrats have gained support from one week ago, when they led by 8.4 points (48.3 percent to 39.9 percent). One month ago, the Democrats had a 7.6-point advantage, 47.4 percent to 39.8 percent.





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