For all the chatter on how that latest revelation about President Trump is the one thing that is finally going to take him down, there has been remarkably little movement in his polling numbers. And as Trump will often remind you, his base is still very much onboard.

He uses fake numbers, yes, but the point broadly stands. It’s not 95 percent of Republicans who approve of him, as he claims, but it is somewhere between 85 and 90 percent in most polls. And as he fights off impeachment, keeping his base intact will be key to making sure GOP lawmakers who are clearly uncomfortable with what he has done don’t desert him.

That said, a new poll suggests we shouldn’t oversell just how solid Trump’s base firewall is.

The AP-NORC poll pegs Trump’s approval rating at 42 percent and his approval among Republicans at 85 percent — both very much in line with other polls.

But when it asks people to dig a little deeper into their feelings about Trump, things start to get sketchier.

Polls have long showed even many Republicans don’t think the man who has uttered more than 13,000 false or misleading claims as president is particularly honest. And that’s certainly the case in this poll. Only 53 percent of Republicans say the word “honest” describes Trump very or extremely well. Another 27 percent say it describes him only moderately well, while 20 percent say it doesn’t describe him very well or at all. That’s still 8 in 10 Republicans who say Trump is at least moderately honest, but moderately honest isn’t exactly a compliment. This and other polls give lie to the idea that Trump’s base gobbles up everything he says as gospel.

The poll also shows 33 percent of Republicans say Trump doesn’t make them “proud.” That’s notably worse than in a March CNN poll, which found 16 percent of Republicans said Trump wasn’t “someone you are proud to have as president.” And 39 percent say the word “disciplined” describes Trump very or extremely well.

1 in 3 Republicans say Trump doesn't make them feel "proud" -- Does Trump make you feel proud? (among Republicans only)

But maybe the most troubling finding for Trump — both when it comes to impeachment and his 2020 reelection bid — is this one: 41 percent of Republicans say that Trump doesn’t make them feel excited.” A strong majority (58 percent) says Trump does make them feel excited, but this is still 4 in 10 Republicans who aren’t excited about their Republican president.

That’s hardly the kind of base discipline you would want to brag about. And it’s a far cry from the raucous support you see at Trump’s rallies.

Regrettably, we don’t have any similar poll questions to compare it to, so we don’t know if this represents any kind of erosion in GOP excitement about Trump. By contrast, in fact, polls have generally showed both Republicans and Democrats are unusually enthusiastic about voting in the 2020 election. Perhaps they don’t need to be excited to turn out.

But as Trump finds himself embroiled in more and more controversies and facing more and more evidence that he sought to leverage a foreign country for politically helpful investigations, it’s worth keeping an eye on numbers below that top-line approval rating among Republicans.

It matters not just how many Republicans approve of Trump when given a binary approve/disapprove choice but how proud and excited they are about defending and voting for him. If the tailing-off that we see in these numbers is repeated in other polls — and some other polls have shown limited but significant Republican support for impeachment — it might give GOP lawmakers more berth to ask tough questions. It would also suggest Trump’s already difficult reelection math is even more difficult than it appears at first glance.