Rep. Alexandria Ocasio-Cortez was quick to respond to President Donald Trump when he dismissed her criticism on Monday.

After saying she had gotten "under his skin," the new congresswoman joked that the president wouldn't be taxed at her proposed 70% marginal rate for the superrich because, she speculated, he's not actually superrich.

"I'd say we'd be taxing 70% of Trump's income, but he probably hasn't made more than $10 million in years — and that's the real reason he's hiding his taxes," Ocasio-Cortez tweeted, adding a winking emoji.

Rep. Alexandria Ocasio-Cortez has been known to clap back at her critics online, and she made no exception when President Donald Trump said on Monday that he didn't care that Ocasio-Cortez had called him a racist.

The 29-year-old lawmaker said Trump's dismissive remark showed that she had gotten "under his skin."

"I bartended for *years* in New York City. I understand guys like this like the back of my hand. We got under his skin," she tweeted, adding a laughing emoji.

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Ocasio-Cortez joked that her proposed 70% marginal tax rate for those who make more than $10 million a year wouldn't apply to Trump because, she speculated, he hasn't met that income threshold in years. Trump has refused to make any of his tax returns public, so it is unclear how much he makes or has historically made, though it has been estimated at far above $10 million.

"I'd say we'd be taxing 70% of Trump's income, but he probably hasn't made more than $10 million in years — and that's the real reason he's hiding his taxes," she tweeted, with a winking emoji.

Ocasio-Cortez, a New York Democrat who represents parts of the Bronx and Queens, has rarely talked publicly about the president, preferring to focus her criticism on her own party and structural issues she's identified in American politics, including the influence of money.

But in a recent interview with "60 Minutes," she argued there is "no question" that the president is a racist.

"When you look at the words that he uses, which are historic dog whistles of white supremacy, when you look at how he reacted to the Charlottesville incident, where neo-Nazis murdered a woman, versus how he manufactures crises like immigrants seeking legal refuge on our borders, it's night and day," she said.