In this Feb. 13, 2018, file photo Marie Newman speaks with supporters at a campaign event in LaGrange, Illinois. (AP Photo by Sara Burnett, File)

WASHINGTON (AP) — Rep. Alexandria Ocasio-Cortez is making her first endorsement of a liberal challenger to an incumbent House Democrat, backing Marie Newman in the primary against eight-term Rep. Daniel Lipinski in Illinois.

The New York congresswoman for now is putting her name and small-dollar fundraising ability behind congressional candidates, rather than in the presidential primary.

Lipinski, who opposes abortion rights, is among the more conservative Democrats in the House and defeated Newman in a primary last cycle.

By backing a primary opponent to a colleague, Ocasio-Cortez is mounting a campaign strategy that resembles her own political rise last year, when she toppled a House Democratic leader in a stunning primary challenge. It’s a flex of power for the freshman lawmaker but also one that makes colleagues wary.

Last week Ocasio-Cortez endorsed Democratic Massachusetts Sen. Ed Markey, who faces a potential primary challenge from Rep. Joe Kennedy III. Markey is a co-sponsor of Ocasio-Cortez’s “Green New Deal” proposal.

Justice Democrats, a group aligned with Ocasio-Cortez that has backed Newman and several other challengers to incumbent lawmakers in the House, announced the endorsement Tuesday.

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