(CNN) The big headline from CNN's new national poll was this: Donald Trump is at his highest approval rating in nearly a year.

Yes, as Trump critics note, 42% approval isn't exactly great. And as the one and only Harry Enten points out , Trump's approval rating gains look less impressive when viewed over the broader sweep of his time in office.

That said, Trump was at 35% approval in a February CNN poll and at 42% in a March CNN survey. That's a gain worth exploring. Which I did.

Here are four subgroups among which Trump performed significantly better in March than he did in February:

Men. Trump was at 50% approval in March as compared to 42% approval in February. Young voters. In February, just 1 in 5 voters aged 18-34 approved of how Trump was handling the job. In March, that number increased to 30% Middle-aged voters. Trump's gains among the young(ish) were one-upped by his showing among those between 35 and 49 years old, where he gained 9 points in approval in a month. College graduates: A group that has long been resistant to Trump had the biggest change of heart toward him between February and March: A 10-point swing.

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