Rep. Alexandria Ocasio-Cortez Alexandria Ocasio-CortezOn The Money: Anxious Democrats push for vote on COVID-19 aid | Pelosi, Mnuchin ready to restart talks | Weekly jobless claims increase | Senate treads close to shutdown deadline McCarthy says there will be a peaceful transition if Biden wins Anxious Democrats amp up pressure for vote on COVID-19 aid MORE (D-N.Y.), the progressive freshman lawmaker who ousted a longtime incumbent in the midterms last year, is backing a challenger hoping to unseat one of the most conservative House Democrats in an Illinois race.

Ocasio-Cortez announced her endorsement of Marie Newman Tuesday. It is the first endorsement the congresswoman has made in the 2020 House races.

Newman is running against Rep. Dan Lipinski in Illinois’s 3rd Congressional District. She lost to the incumbent in 2018 by just more than 2,000 votes. ADVERTISEMENT

“Marie Newman is a textbook example of one of the ways that we could be better as a party — to come from a deep blue seat and to be championing all the issues we need to be championing,” Ocasio-Cortez told The New York Times.

“The fact that a deep blue seat is advocating for many parts of the Republican agenda is extremely problematic. We’re not talking about a swing state that is being forced to take tough votes,” she added.

Newman said in a statement sent by Justice Democrats, a group that backs progressive candidates including Newman and Ocasio-Cortez, that she is “thrilled” to have the endorsement.

“The momentum is growing in our movement to make the Democratic Party fight for solutions as big as the problems we face and create a party of voters, not corporate donors,” Newman said.

Newman supports progressive proposals such as "Medicare for All" and the Green New Deal.

She has also picked up endorsements from two Democratic presidential candidates, Sens. Bernie Sanders Bernie SandersSirota reacts to report of harassment, doxing by Harris supporters Republicans not immune to the malady that hobbled Democrats The Hill's Morning Report - Sponsored by Facebook - Republicans lawmakers rebuke Trump on election MORE (I-Vt.) and Elizabeth Warren Elizabeth WarrenOvernight Defense: Appeals court revives House lawsuit against military funding for border wall | Dems push for limits on transferring military gear to police | Lawmakers ask for IG probe into Pentagon's use of COVID-19 funds On The Money: Half of states deplete funds for Trump's 0 unemployment expansion | EU appealing ruling in Apple tax case | House Democrats include more aid for airlines in coronavirus package Warren, Khanna request IG investigation into Pentagon's use of coronavirus funds MORE (D-Mass.).

Lipinski is an anti-abortion Democrat who faced his toughest primary challenge in 2018, with progressive lawmakers breaking with House Democratic leaders' support for him.

Among those leaders was then-Rep. Joseph Crowley, at the time the House Democratic Caucus chairman, whom Ocasio-Cortez beat in the Democratic primary for New York's 14th District.