(CNN) President Donald Trump is staring down possible impeachment. Fortunately for him, his base of very conservative Republicans in the Senate likely would save him from being removed from office.

But CNN/SSRS polling in September suggests that Trump should be more worried about a part of the Republican Party that gets less notoriety: the more moderate part. This part of the party won't play a large role in impeachment proceedings, but their feelings toward impeachment and Trump in general could hurt his re-election bid.

The yearning for impeachment and removing Trump from office has risen significantly among moderate and liberal potential Republicans (i.e. Republicans and Republican leaning independents). Nearly a third of moderate/liberal potential Republicans in our latest CNN poll said they wanted Trump impeached and removed last week, while about two-thirds didn't want that. Back in late May, the split was 16% for impeachment and removal and 81% against it. This is statistically significant movement.

The seeming shift of this moderate/liberal potential Republican bloc shouldn't be too surprising, given what a different CNN poll found in early September. In that poll, 25% of moderate/liberal potential Republicans disapproved of the job Trump was doing as president. Only 69% approved. Trump's job approval ratings with this moderate/liberal Republican bloc looks like the percentage who want him impeached and removed from office.

Now compare what's going on with the very conservative part of the Republican Party. Among those who are very conservative and can be classified as potential Republicans, Trump remains a very popular president. His approval rating in CNN's early September poll among very conservative potential Republicans was 94%, about 25 points higher than his rating with the moderate to liberal wing of the party.

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