On Saturday afternoon, Rep. Alexandria Ocasio-Cortez, D-N.Y., made her endorsement of Sen. Bernie Sanders, I-Vt., official at a rally in Queens, N.Y., that marked Sanders' return to the campaign trail after recently having a heart attack.

"I'm in the United States Congress now," said Ocasio-Cortez as she gave a 20-minute speech introducing Sanders, "a long, long way from being a sexually harassed waitress in downtown Manhattan one year ago."

"The halls of Congress are no joke," she continued.

"It is no joke. Standing up to corporate power, and established interests is no joke. It's not just about standing up and saying these things, but behind closed doors, your arm is twisted, the vise pressure of political pressure gets put on you, every trick in the book, psychological, and otherwise is to get us to abandon the working class," she said before a massive crowd.

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Ocasio-Cortez said that the pressure she'd felt in Congress led her to "appreciate the enormous, consistent, and non-stop advocacy" of Sanders.

The 30-year-old New York Democrat has served as a lightning rod in Congress and a frequent target of criticism on the right as one of the most outspoken House Democrats.

She has attracted much more attention than a freshman member of Congress might otherwise receive, becoming an outspoken voice on high-profile issues like student debt, D.C. statehood, and climate change.

Sanders said during his speech that he planned to campaign with Ocasio-Cortez, ensuring that Ocasio-Cortez will continue to have a high-profile role in the presidential campaign.

President Donald Trump has frequently criticized her, and retweeted a post from the Republican Party Twitter this afternoon that criticized Ocasio-Cortez and Rep. Ilhan Omar, D-Minn., as "far-left Democrats" who wanted to "spend taxpayer dollars & have the government take control over every aspect of American life."

Ocasio-Cortez seems aware of the criticism and often responds sharply. Last week, she was the subject of a story in the conservative Washington Times that had criticized her for the cost of her hairstyle.

"They’re just mad we look good doing it," she had said on Twitter of her conservative critics, adding the hair flip emoji.

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She addressed the issue in her speech today as well.

"You all like my haircut. It got a lot of attention last week," she joked at the beginning of her speech.