Rep. Alexandria Ocasio-Cortez slammed former Wisconsin Gov. Scott Walker's simplification of her proposal to hike taxes on the super-rich in a tweet on Tuesday.

Walker said he told a group of fifth graders that the policy amounted to their grandmother taking 70% of their $10 pocketmoney.

In a viral takedown, Ocasio-Cortez pointed out that the proposed marginal tax rate increase would only apply to the wealthiest Americans.

Rep. Alexandria Ocasio-Cortez is playing offense on her proposal to hike taxes on the superrich.

In her latest attempt to clarify the policy — and counter conservative attacks on it — Ocasio-Cortez slammed Wisconsin's former Republican Gov. Scott Walker after he shot the proposal down with a simplistic joke.

In a Tuesday tweet, Walker said he told a group of fifth graders that Ocasio-Cortez's proposed 70% marginal tax rate on income over $10 million was akin to having 70% of their $10 in pocket money taken by their grandmother.

"'Imagine if you did chores for your grandma and she gave you $10. When you got home, your parents took $7 from you.' The students said: 'That's not fair!'" Walker wrote. "Even 5th graders get it."

Read more: THE TRUTH ABOUT ALEXANDRIA OCASIO-CORTEZ: The inside story of how, in just one year, Sandy the bartender became a lawmaker who triggers both parties

Walker's tweet provoked backlash even before the congresswoman got around to mocking it.

"Explaining marginal taxes to a far-right former Governor: Imagine if you did chores for abuela & she gave you $10. When you got home, you got to keep it, because it's only $10," Ocasio-Cortez wrote, imitating Walker's tweet. "Then we taxed the billionaire in town because he's making tons of money underpaying the townspeople."

Ocasio-Cortez made waves when she announced her support for a 60-70% marginal tax rate on annual income above $10 million during an interview with "60 Minutes" in early January. Many progressive economists have come to her defense, arguing that the policy is good economics, while conservatives have characterized the proposal as radical socialism.

After President Donald Trump on Monday dismissed Ocasio-Cortez's charge that he is a racist, the 29-year-old lawmaker used the opportunity to sell her tax proposal with a bit of humor.

Retweeting the president's comment about her she wrote, "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," adding a winking emoji.

Ocasio-Cortez on Tuesday called her marginal tax rate proposal "a cornerstone policy" of any plan to reduce income and wealth inequality in the US.

The new congresswoman told INSIDER earlier this month that she also supports deficit spending and reducing the military budget, among other methods, to fund social policies like the Green New Deal and tuition-free college. And she said Modern Monetary Theory, a burgeoning theory that the federal debt is not an economic restraint for the US, should be "a larger part of our conversation."