Warren and Senator Cory Booker, among others, have recently endorsed the idea of a "Green New Deal", a call to reimagine an environment-first economy that would phase out fossil fuels. Ocasio-Cortez thrust that issue into the national dialogue after she joined a sit-in protest in the office of incoming House speaker Nancy Pelosi in one of her first, rebellious acts in Washington. Loading Her rise has stirred a backlash among some congressional Democrats, who are seeking to constrain her anti-establishment streak and fear her more radical ideas could tar the party as socialist. Back home in New York, she has stoked opposition to a deal with Amazon to set up offices in Queens, putting pressure on Governor Andrew Cuomo and Mayor Bill de Blasio, both Democrats, to justify corporate incentives. Ocasio-Cortez, a Bronx-born 29-year-old of Puerto Rican descent, is the youngest congresswoman ever, and Washington veterans say they cannot recall a similar congressional debut.

"A bartender from the Bronx has been able to create a litmus test around climate and economic policy for every 2020 Democrat," said Waleed Shahid, who was one of Ocasio-Cortez's early campaign advisers and is now communications director for Justice Democrats, a liberal activist group. Alexandria Ocasio-Cortez arrives in Washington for orientation for new members of Congress. Credit:AP Far beyond policy, she has emerged as a potent symbol for a diversifying Democratic Party: a young woman of colour who is giving as good as she gets in a political system that has rarely rewarded people who look like her. Her mastery of social media has allowed her to connect with audiences who might otherwise be alienated from Washington. Still, her unexpectedly outsize profile could bring perils. Her threats to knock out more moderate Democrats in future primaries in particular seem to have rankled. Some whisper her tweet-first, ask-questions-later mentality reminds them of President Donald Trump. And while she has attracted considerable attention, policymaking in Congress remains a long, slow grind dominated by insiders. Pelosi, for instance, declined to grant the new climate change committee some of the powers that Ocasio-Cortez had demanded at the sit-in.

Many Republicans are downright giddy at the notion that a self-described democratic socialist is driving Democratic policy discussions. Congressional Republicans saw up close the dangers of having the more staunchly right-wing elements of the Tea Party come to define their tenure in the House majority. "Whether Democrats like it or not, Congresswoman Ocasio-Cortez is now the face of their party," said Steven Cheung, a former communications adviser in the Trump White House. Yet Republicans face their own risks if their attacks on her are perceived as sexist or condescending. "Over 200 members voted for Nancy Pelosi today, yet the GOP only booed one: me," she wrote on Twitter on January 3. "Don't hate me cause you ain't me, fellas." It has already been retweeted nearly 50,000 times.

Supporters and rivals alike agree that she has upended the traditional rules of engagement on Capitol Hill with a Millennial's intuitive sense of what sells online - all before she has hung anything on her barren office walls or even found a permanent place to live. In an interview, Ocasio-Cortez rejected "the general notion of, 'Oh, you're here and need to be quiet and keep your head down'". "For me, especially as a member who won her seat via a primary election against another Democrat, my constituency was telling me the exact opposite thing," she said. Republicans, she said, fundamentally misunderstand her: "They think I'm just a Tea Party mirror. It's an easy and convenient way to frame something. But I don't think it's the same." Still, she has fully embraced the radical label - especially if it means pulling the Democratic Party to the left. "I think that it only has ever been radicals that have changed this country," she told 60 Minutes.

It has all come in a rush: By the end of her full first day as a congresswoman, Ocasio-Cortez had overtaken Pelosi's following on Twitter. Her initials and Twitter handle, @AOC, have become shorthand for the phenomenon that is the talk of Capitol Hill. She had a full 60 Minutes segment devoted to her on her first Sunday as a congresswoman. She was the first politician that MSNBC turned to after Trump's first Oval Office address for analysis on what was Rachel Maddow's most-watched show ever. And she has become a viral internet sensation many times over, including one video of her dancing outside her office that has topped 22 million views across the globe. She's a draw on the right as much as the left: Fox News spent more than two hours covering her first five days in Congress, according to a tally by Media Matters, the liberal media watchdog group. MSNBC spent 52 minutes and CNN 96 minutes talking about her in that span. In a recent Instagram chat - live from her kitchen with several thousand fans watching - Ocasio-Cortez outlined her strategy to "shape the national narrative" while chopping vegetables for an Instant Pot recipe. "In Trump's America," she explained, "I'm not a big fan of bipartisanship."

On the environment, she said that her goal was to move the boundaries of debate far enough to the left that a carbon tax would look like the moderate option, compared to "wildly ambitious" direct government intervention imagined in the Green New Deal. Perhaps Ocasio-Cortez's most talked-about idea has been that people she called "the tippy tops" - those earning above $US10 million ($14 million) - should pay a 70 per cent rate on income above that threshold. The remark set off days of debate among economists and pundits, on the right and the left, about tax rates unseen in America in decades but common during the post-World War II era. "I've been trying to open up this rhetorical space for many, many years," said Stephanie Kelton, a former chief economist for Democrats on the Senate Budget Committee. "They used to talk about the Oprah effect," said Kelton, now a professor at Stony Brook University. "I think it's the Ocasio effect at this point." Julian Castro, the former mayor of San Antonio and federal housing secretary who is running for president, was shown the clip of Ocasio-Cortez's tax comment during an interview with ABC's George Stephanopoulos - and then went even further than her.

"As you know, George, there was a time in this country where the top marginal tax rate was over 90 per cent," Castro explained. "Even during Reagan's era in the 1980s it was around 50 per cent." Ocasio-Cortez was still glowing about it days later. "It's so incredible to see," she said in the interview. "First we had Elizabeth Warren come out and talk about a Green New Deal. Next we have Julian Castro defending marginal tax rates and he basically is saying we've had 90 per cent-plus in the past. It's totally changing the conversation." She has had some stumbles, including sparring with fact checkers after The Washington Post gave her "four Pinocchios" for a false claim about Pentagon spending. "I think that there's a lot of people more concerned about being precisely, factually, and semantically correct than about being morally right," she said on 60 Minutes. She added she seeks to correct and acknowledge her mistakes as she makes them, unlike Trump.

The arc of Ocasio-Cortez's ascent is well known: A former bartender and organiser for Bernie Sanders' 2016 presidential campaign, she shocked the political world by ousting Joseph Crowley, who had been in line to succeed Pelosi as Democratic leader. It was the biggest primary defeat for a Democrat in 2018. In the days after that primary victory, Kirsten Gillibrand of New York, a likely presidential candidate in 2020, became the first senator to join Ocasio-Cortez in her call to "abolish ICE," the Immigration and Customs Enforcement agency. "She absolutely does have the ability to put issues on the map," said Pramila Jayapal, a Seattle-area Democrat and a leader of the Congressional Progressive Caucus. "It's not that there haven't been champions of these issues before. But when you've got 2.1 million Twitter followers and a press that will cover anything you say, it's a huge opportunity for us." The sheer brightness of her star has evoked more than a few eye rolls among House institutionalists. Most colleagues do not know quite what to make of her just yet. "I love Alexandria Ocasio. I saw her in her 60 Minutes interview. I thought she was great," said Adriano Espaillat, a 64-year-old Democrat from a neighbouring district that includes part of the Bronx. "She is like one of our daughters. You know, she could be my daughter, one of anybody's children. She's an adult, obviously. But you know I love her. She's sharp, has a great smile, intelligent, is liberal, progressive. I think she has great ideas, bold ideas."

For all her focus on what she called "outside-inside" organising, Ocasio-Cortez does seek power inside the Capitol. She raised her hand for a slot on the powerful Ways and Means Committee, though no freshmen got a seat on that panel. She has since secured the backing of the New York delegation for a spot on the Financial Services Committee, which would be a notable perch for a politician who has railed against the grip of money in politics generally, and Wall Street in particular. But when it comes to navigating internal House dynamics, her decision to support an effort by Justice Democrats to recruit Democratic primary challengers in 2020 - virtually unheard-of in the cordial Capitol corridors - has left colleagues unnerved and less than trusting. She did push back against a report in Politico that she was recruiting a challenger to Hakeem Jeffries, the highest-ranking New York Democrat in House leadership.

Asked about Ocasio-Cortez's splashy entrance into Congress, Jeffries instead went through the names of every other incoming New York member, listing her last. "I don't think singling out one over the other is the appropriate thing for me to do, at least at this moment," Jeffries said as he left a recent gathering of the New York Democratic delegation that she also attended. As for the primary-challenge matter, he said he and Ocasio-Cortez had not spoken about it. "I've said hello," Jeffries said. "We haven't talked about any particular issue beyond the logistics of her arrival into the United States Congress." The New York Times