Pro-Israel groups have heralded the defeat of a leading Democratic contender for Congress after pouring millions of dollars into blocking her election, for failing to be sufficiently supportive of Israeli government policies.

Donna Edwards, who was for months the favourite to win the primary for a safe seat in Maryland, lost to Glenn Ivey on Tuesday after the American Israel Public Affairs Committee (Aipac) and allied groups waded into the race.

Aipac proclaimed Ivey’s victory, by 51% to 35%, as evidence that “being pro-Israel is both good policy and good politics”.

Edwards’s defeat will be taken as a warning by other Democratic contenders not to criticise Israeli policies, or risk a well-funded campaign against them.

Aipac and its allies spent nearly $7m through political action committees to block Edwards, who served eight years as the first Black woman elected to Congress from Maryland before losing a bid for the Senate in 2016.

Edwards was endorsed by the House speaker, Nancy Pelosi, and other leading Democrats.

But she angered some pro-Israel groups during her earlier stint in Congress by failing to back Israeli attacks on Gaza and for her support of the Obama administration’s nuclear deal with Iran when it was strongly opposed by the Israeli government.

Following Ivey’s victory, Aipac declared it had helped nine “pro-Israel Democrats defeat their anti-Israel opponents in 2022!”.

Another group, Pro-Israel America, also heralded Edwards defeat.

It said: “Ivey’s victory once again demonstrates that strong pro-Israel stances are both good policy and politics, as his commitment to advancing the US-Israel relationship starkly contrasted with the positions of the candidate he defeated.”

However, the campaign against Edwards rarely focused on her positions on Israel and much of the spending that went to saturate the airwaves with hostile advertising questioning her work ethic came from Republican billionaires.

Aipac’s political action committee, the United Democracy Project, has received substantial donations from Trump campaign funders Paul Singer and Bernie Marcus, as well as the billionaire Israeli-American Democratic donor, Haim Saban.

A more liberal pro-Israel group, J Street, which backed Edwards, said it was “extremely alarmed” by the part played by Aipac’s money in deciding Democratic races.

“They targeted [Edwards] for defeat simply for holding principled, mainstream Democratic views about US diplomatic leadership in the Middle East, while their spokespeople baselessly smeared her as ‘anti-Israel’. It’s a deeply harmful trend we’ve seen again and again in this cycle.”

J Street has warned that Aipac and its Republican funders are trying to drive the Democrats “into more rightward direction on Israel and foreign policy” by intimidating candidates into “feeling that they cannot offer good faith criticism of Israeli policy, that they cannot vocally support Palestinian rights”.