Since Alexandria Ocasio-Cortez beat 10-year incumbent Rep. Joe Crowley (D–N.Y.), election watchers have been on alert for upsets in other states by similarly progressive and Democratic socialist candidates. Thursday, an Ocasio-Cortez–style candidate failed to clear a primary hurdle in Delaware.

The Senate race between Sen. Tom Carper (D–Del.) and Kerri Evelyn Harris, an Air Force veteran who is also black and gay, ended in a defeat for Harris. As FiveThirtyEight notes, the fight for Delaware's next senator mirrors Ocasio-Cortez's race. Carper, who has never lost an election, spent 42 years serving as the state's sole congressman, governor, and finally, as a senator. Harris was not even born when Carper was first elected to statewide office.

There are other similarities as well, including the fact that Harris is much more progressive than her challenger. Carper is considered the sixth-most conservative Democrat in the Senate. According to Harris' campaign website, she supports legislation such as Medicare for all, raising the minimum wage to $15 an hour, stronger gun control measures, and a tax on large corporations for employees who use government assistance programs. Similarly, Harris was greatly outspent by Carper—$3.3 million to her $69,000.

Delaware's senate race shed light on an ideological divide in the Democratic party. Harris received endorsements from Ocasio-Cortez and and the Our Revolution PAC, which is associated with Sen. Bernie Sanders (I–Vt.). The group that worked on Ocasio-Cortez's campaign also backed Harris. Conversely, former Vice President Joe Biden recorded a robocall in support of Carper.

Prior to Harris' loss, Ayanna Pressley managed to pull off an upset against Rep. Michael Capuano (D–Mass.) in the Bay State's 7th Congressional District. Capuano was first elected into office in 1998. Pressley was no stranger to political office (she worked 16 years as a congressional aide and served nine years as a Boston city councilor) and her opponent had a strong progressive streak. Still, Pressley enjoyed an endorsement from Ocasio-Cortez on Twitter.

Harris joins several other democratic socialist candidates who have lost their races so far this year.