President Trump’s strategy for rebuffing allegations that his campaign colluded with the Russian government last year is two-fold: Undermine the investigations, even as he claims — as he has done unwaveringly from Day One — that there is no collusion to be found. Polling, including a new poll from AP-NORC, shows that, among his base, it works.

Trump used both of those strategies during a brief talk with reporters Friday morning as he made his way to the FBI building for an event.

First, he undercut the Justice Department’s investigation into Russian meddling by way of disparaging the FBI and its agents who are working with special counsel Robert Mueller.

“It’s a shame what’s happened with the FBI,” Trump said. “But we’re going to rebuild the FBI. It’ll be bigger and better than ever. But it is very sad, when you look at those documents,” presumably a reference to the text messages from a former Mueller team member that criticize Trump, “and how they’ve done that is really, really disgraceful. And you have a lot of very angry people that are seeing it. It’s a very sad thing to watch, I will tell you that. … when everybody — not me — the level of anger with respect to what they’ve been witnessing at the FBI, it’s certainly very sad.”

The AP-NORC poll asked about how the public viewed the Mueller investigation both in June and this month. Overall, there’s been no change: About a quarter of Americans are extremely or very confident that the probe will be fair and impartial. Another 36 percent are moderately confident of that.

If we break out that top-line number by party, though, the picture shifts. Overall, the same number of people say they’re very confident the probe will be impartial, but that hides a spike in confidence among Democrats and a plunge in confidence among Republicans.

As we noted earlier this week, this is Trump’s explicit strategy: Convince his base that the investigations are both meritless and fruitless. This survey reinforces that the strategy is working.

Most Americans, the AP-NORC poll found, think that Trump did something either illegal or unethical in relation to Russia. Again, though, we see a wide partisan split. Most Democrats think he probably broke the law; most Republicans think he did nothing wrong.

This is a function of that second rhetorical point that Trump propogates: Nothing to see here.

“Let’s put it this way: There is absolutely no collusion,” Trump said Friday morning. “That has been proven. When you look at the committees, whether it’s the Senate or the House, everybody — my worst enemies — they walk out, they say, ‘There is no collusion, but we’ll continue to look.’ They are spending millions and millions of dollars, and there is absolutely no collusion. I didn’t make a phone call to Russia. I have nothing to do with Russia. Everybody knows it.”

It has not been proven that there was no collusion. It has also not been proven that there was direct collusion between Trump himself and Russian actors, but that lack of proof isn’t proof that collusion is lacking.

That said, though, there is an interesting bit of data that underlies this point.

Over the course of the year, views of whether or not Trump or his campaign had contacts with the Russian government largely haven’t changed, despite the flood of revelations about how and where the campaign had contacts with the Russian government.

From March to December, the percentage of respondents who are extremely or very concerned about inappropriate contacts ranged from 44 percent to 48 percent. The percentage who were not very or not at all concerned ranged from 30 percent to 36 percent.

Since June, when the percentage of those saying they basically weren’t concerned rose, we have found out that:

  • Trump’s son, son-in-law, Jared Kushner, and then-campaign chairman Paul Manafort met with a Russian lawyer after being promised dirt on Democratic presidential nominee Hillary Clinton.
  • A campaign adviser spoke repeatedly with people linked to the Russian government to set up a meeting between Trump and Russian President Vladimir Putin.
  • Trump’s campaign chairman offered to give private briefings to an oligarch linked to Putin.

Despite those revelations — none of which necessarily proves collusion based on what we know at the moment — Americans essentially express no more concern about the campaign’s actions than they did in March.

The takeaway is pretty unavoidable. Views of the investigation and the findings are sharply divided by party.

Take, for example, the question of whether Trump tried to obstruct the investigation. Since June, there’s been little change in the overall number.

But there’s also been little change in the numbers by party. In June, the Associated Press wrote, nearly nine in 10 Democrats and only a quarter of Republicans said they thought Trump tried to impede or obstruct the investigation. In December, those numbers were 86 percent and 24 percent, respectively. No change.

This may be linked to the findings about views of the Mueller investigation. If you see the indictments being handed down by Mueller but are predisposed to believe that the president and his campaign did nothing wrong, you may be more inclined to assume that the problem lies not with Trump but with the investigation. That conservative media outlets are hyping this point only makes it more likely that you would do so.

The fairest interpretation of the moment is that we’ve reached a point of partisan stasis, where those who support Trump — including the president himself — will not be swayed from their position that he did nothing wrong. Perhaps he didn’t; the verdict is still out, to use an apt metaphor.

Should something more serious and obvious emerge in those investigations, though, the natural question is a disconcerting one: Which will prevail, confidence in our institutions or partisanship?