WASHINGTON, Nov 4 - Democrats’ takeover of Congress and growing Republican unease over Israel could trigger the biggest reassessment of US support for its closest Middle East ally in decades, after an election shaped in part by anger over the Iran war. Democrats won both the Senate and House in Tuesday’s midterms.

Many winning candidates were progressives who campaigned against military aid to Israel and the US-Israeli war on Iran. Israel’s campaign in Gaza and Prime Minister Benjamin Netanyahu’s embrace of President Donald Trump and other Republicans had already strained decades of bipartisan support for Israel.

Democratic control could bring greater scrutiny of military aid and West Bank violence, along with hearings and challenges to Trump nominees, although the president’s veto limits the party’s ability to force major policy changes.

One successful progressive was Abdul El-Sayed of Michigan, the first Muslim elected to the US Senate despite Republican attempts to win over Jewish voters who might have been uncomfortable with his faith and his criticism of Israel.

There were also signs that Republicans might reexamine their party's traditional support for Israel.

Vice President JD Vance on Wednesday blamed the election rout on the war against Iran and identified Israel as an issue for Republicans.

He said in a social media post that one pollster identified four actions that would bring disgruntled Trump voters back: "1) End the war 2) Focus on cost of living/inflation 3) Put America First 4) Change our relationship to Israel." Trump announced in a Fox News interview on Tuesday that he had made a deal with Netanyahu that Washington would end annual security assistance to Israel. However, it was not immediately clear that he had the legal authority to stop the billions of dollars in military assistance Washington sends Israel each year.

Policy toward Israel has emerged as a generational divide in US politics.

Opinion polls show younger voters, including some Republicans, feel the country has been too supportive of Israel and insufficiently supportive of residents of the Palestinian territories. SENTIMENT SHIFTING Congressional sentiment had already been shifting.

In September, 46 of the 47 members of the Senate Democratic caucus voted for a resolution to force Trump's administration to report to Congress on increasing violence against Palestinians by Israeli settlers in the West Bank. Republicans blocked the measure, but the near-unanimous Democratic vote was a sharp departure from decades of reliable bipartisan backing for Israel.

Democrats will likely focus again on West Bank violence. "We need to make sure that we apply our laws and international law and our policies uniformly across the board when it comes to the actions of countries.

There should not be an Israel exception," said Democratic Senator Chris Van Hollen of Maryland, who has led attempts to put human rights conditions on Israel aid.

Democrats’ power remains limited, however. Trump promised to be “Mr. Veto,” and they are unlikely to muster the two-thirds majorities needed to override his vetoes if the president refuses to sign their bills.

Still, there might be enough resistance to sending US tax dollars abroad, and anger over the Iran war, for the "America First" wing of the Republican Party to also push back.

The election result could see "weird bedfellows of left and right come together in condemnation of Israel," said Price Floyd, a former US official and senior adviser with Argyll Strategy, a London-based strategic communications firm.

MAKING NOISE Majorities also mean Democrats can summon administration officials to public hearings, a rarity under Trump's Republicans.

"What Congress can do is they can make ... a lot of noise. They can threaten to hold up nominees.

They can create lots of questions about various assistance deals and force the president to do waivers (if he lifts sanctions)," said William Wechsler, senior director of Middle East programs at the Atlantic Council. Opinion polls showed the Iran war was a top election issue.

Many Americans blamed higher prices – especially for gasoline – on the conflict Trump began in February. Jonathan Schanzer, executive director of the Foundation for Defense of Democracies think tank, which advocates for a strong US-Israel alliance, said Israel's changing leadership could change the "mood music" of dealings between the two countries.

Netanyahu lost his governing majority in an October 27 Israeli election, but denied opponents a clear path to unseat him. Negotiations to form a new government are expected to be protracted.

A new Israeli government, particularly one less closely tied to Republicans, could engage in a more cooperative way with Democrats, Schanzer said.

"Nothing is going to change in the United States until January when Congress takes their seats and by then, there may be a new Israeli government that would also have an impact on this," Schanzer said.