Four Democrat candidates backed by a socialist organization won their primary elections for the Pennsylvania state House on Tuesday evening.

The four candidates—backed by the Democratic Socialists of America (DSA)—won in Philadelphia and Pittsburgh, two cities that lean heavily Democrat.

DSA members Sara Innamorato and Summer Lee won the Democrat primaries for state House races in Districts 21 and 34—located in the Pittsburgh area.

Lee won against incumbent Rep. Paul Costa (D-Wilkins), and Innamorato defeated incumbent Rep. Dom Costa (D-Stanton Heights) by running campaigns to the left of the two state House members.

“It’s not even close,” Paul Costa, 58, told the Pittsburgh Post-Gazette after calling Lee to congratulate her. “Their campaign did a lot better job of getting people out to vote. They energized a lot of people, and they showed up at the polls.”

Innamorato and Lee do not have any Republican challengers in the general election.

In the Philadelphia area, Kristin Seale and Elizabeth Fiedler won their respective Democrat primary elections in House Districts 168 and 184. The DSA had backed both Seale and Fielder.

Fiedler, who used to work as a reporter for public radio, defeated Jonathan Rowan and does not have a Republican challenger in the general election. Seale, an executive of an energy conservation nonprofit, will challenge incumbent Rep. Christopher Quinn (R-Media).

Arielle Cohen, the co-chair of the Pittsburgh DSA, called the victories a “monumental shift” in the electorate, pointing out that membership in the organization has grown since Donald Trump won the presidency in 2016.

“We won on popular demands that were deemed impossible. We won on health care for all, we won on free education,” Cohen told HuffPost. “We’re turning the state the right shade of red tonight.”