WASHINGTON – As polls open across the United States, Jewish voters might hold the key to the balance of power in Washington.The fate of the Russia investigation, of the Supreme Court, of sanctions law and immigration policy rests in the Senate, and the fate of the Senate next month rests in a handful of midterm election races in which Jewish voters are playing an essential role.Most political pollsters agree that Democrats have an uphill battle to take back the upper chamber on November 6. The party risks losing as many seats they currently hold as there are Republican-held seats up for grabs. But the possibility of flipping the Senate, and thus of providing a check on US President Donald Trump, is tantalizing to party loyalists. And among those loyalists are a large majority of American Jews. A new poll released last month by the Jewish Electorate Institute found that 74% of American Jews plan on voting for Democrats next month – the same number that plan on voting against Trump’s reelection, regardless of which candidate emerges to challenge him in 2020, suggesting that Jewish voters consider the 2018 midterms an initial referendum on his presidency.This constituency has always mattered in American elections. Concentrated in districts and states often determinative of the balance of power in Washington, Jews vote reliably and in large numbers. But their importance is as clear as ever in this election cycle, as several of the closest and most consequential races could well be decided by Jewish voter turnout.This is most obvious in Florida. Incumbent Democratic Senator Bill Nelson is in a neck-and-neck race with Republican Governor Rick Scott, and polling averages – coupled with historical turnout in non-presidential election years – suggest the race will likely come down to a margin of 50,000-100,000 votes. Roughly 850,000 Jewish residents live in Florida, making this bloc absolutely critical to the outcome of the race.And that formula applies beyond the Sunshine State. In Nevada, Jacky Rosen, a congresswoman who once served as president of her synagogue congregation, now poses a serious challenge to one of the most vulnerable Republican senators up for reelection. In a tight race where the outcome could rest on 15,000 voters, the state’s Jewish population of 78,600 could easily make the difference.Arizona’s 108,000 Jewish voters could tip the balance of a Senate contest there in favor of Kyrsten Sinema, a Democrat in one of the most friendly states for progressives in the country. In New Jersey, where 5.6% of the state population is Jewish, strong turnout could be enough to buoy Bob Menendez – the Democratic incumbent, who recently survived a searing corruption scandal – to reelection. And even in Texas, where an insurgent Beto O’Rourke is challenging incumbent Republican Ted Cruz, the state’s 171,000 Jewish residents may prove decisive in the results of a race now considered too close to call.The JEI poll underscored years of polling that has found that American Jews don’t vote with Israel top of mind: Instead, they vote on issues of pluralism, religious freedom, and social welfare. But several midterm races across the country have touched on the politics of Israel, ostensibly in an effort by candidates to rile their bases of support. Cruz, as an example, has repeatedly targeted O’Rourke for a vote he cast against emergency funding to Israel for the Iron Dome during conflict with Hamas. The senator has characterized O’Rourke, a congressman, as “anti-Israel” for requesting additional time to collect information before casting his vote. O’Rourke, meanwhile, has described himself as a Zionist, supportive of a Jewish state of Israel, while also expressing concern with Israel’s ability to maintain its democratic nature through the continued occupation of Palestinian lands.The GOP has similarly targeted Sinema of Arizona for her “foreign policy problem” of opposing the Iran nuclear deal in 2015 before supporting its continuance in 2017, and for “working with anti-Israel groups,” of which they include Women in Black and Local to Global Justice. Sinema, meanwhile, says she supports “a strong relationship with Israel, our democratic ally in the Middle East.”The effects of these races are not isolated. Those who show up for a contested Senate race are more likely to vote down ballot along their party line, benefiting House candidates in tight races hoping to sweep the lower chamber with a blue wave.And those dynamics have driven the Jewish Democratic Council of America, or JDCA, which closely examined the October poll commissioned by its affiliate JEI as it chooses which races to fund throughout the campaign’s final weeks. “American Jews are particularly negative in their perception of President Trump’s handling of health care, the environment, gun safety, immigration, the Supreme Court and taxes,” the JDCA said in a statement. “The poll also finds widespread disapproval with Trump’s handling of the Iranian nuclear deal, antisemitism, moving the US Embassy in Israel, the US relationship with Palestinians, and US foreign policy overall.”Perhaps the most important finding in the poll of all: Only 6% of those polled said that Trump’s policy on Israel would cause them to consider voting for him, despite disagreements on the other issues that matter to them.“While Jewish voters are split almost evenly on how they respond to the way President Trump is handling US-Israel relations, few are willing to support him on that alone,” they added.