TAMARAC — Republicans can't win the White House without winning Florida, so every presidential election cycle they look longingly at Florida's Jewish voters.

It's such a tantalizingly obvious key to locking down 29 electoral votes: hundreds of thousands of Florida Jews who overwhelmingly vote Democratic.

Just reason with them, the thinking goes. They are disproportionately affluent and well-educated. Surely these Floridians can be persuaded that voting Republican is more in their self-interest, through lower taxes and unwavering support for the conservative government in Israel.

The difference between three-quarters of Florida Jews voting for the Democratic nominee and two-thirds voting Democratic could be 50,000 votes — enough to decide the election.

"We're looking to do whatever we can," said Mark McNulty of the Republican Jewish Coalition, which spent $6.5 million in 2012 trying to sow doubts with Jewish voters about President Barack Obama's commitment to Israel. "In places like Florida and Ohio with substantial Jewish populations, a couple percentage points can mean the difference in an election."

But as much as political groups like the RJC like to say they are steadily gaining ground with Jewish voters, their progress is more accurately measured in inches than miles.

Even amid the falling out between Obama and Israeli Prime Minister Benjamin Netanyahu, as leading Republican presidential candidates argue Obama and Hillary Rodham Clinton made the Middle East less safe, and as Obama critics in Washington and Israel call the emerging nuclear deal with Iran a grave threat to the Jewish state, few experts see Republicans as likely to significantly improve their performance in 2016. Clinton's strong ties to the Jewish community, in fact, could make Jewish voters a harder target for the Republican nominee.

"It's a constant feature of American elections in the past decade. Every time the GOP claims to make inroads, and every time they are disappointed to find the American Jewish community has not changed its behavior," said Shmuel Rosner, a prominent columnist in Israel and political editor of the Jewish Journal.

It doesn't help that many of the Republicans most vocal about their deep love and devotion to Israeli security are Christian conservatives who turn off even staunchly Republican Jews.

"Apart from getting rid of their base — evangelicals — I don't see a way for Republicans to make really deep inroads in the Jewish vote," said Kenneth Wald, a political science professor and the Samuel R. "Bud" Shorstein professor of American Jewish Culture & Society at the University of Florida. "They've essentially got the Jewish voters who they're going to get, and it's essentially the same group they've had for a long time, probably about a fifth to a quarter of the population."

More than 40 years ago, political scientist Milton Himmelfarb noted that Jews are about the only ethnic group not to have grown more conservative as they became more prosperous, quipping that Jews "earn like Episcopalians, and vote like Puerto Ricans."

But Wald credits radio host and comedian Peter Sagal with best summing up the question about Jewish voters that has consumed academics and confounded leading Republican strategists for generations:

"What is it about being rich and white that Jews do not understand?"

• • •

The tip filtered through the newsroom of the Tampa Bay Times earlier this month. Somebody's friend had an elderly mother living in a vast condo complex in Broward County, the kind of overwhelmingly Jewish retirement community as familiar to Democratic politicians in Florida as to fans of the TV show Seinfeld. Supposedly this lady's Democratic Club was loaded with people either ambivalent about Hillary Clinton running for president or downright hostile to her candidacy.

That would be a stunning development. Tepid support among elderly Jewish Democrats, expected to be among Clinton's most loyal constituencies, would signal serious trouble for the likely Democratic nominee.

Nowhere are the political stakes higher than Florida, the nation's biggest battleground state where Jewish voters represent anywhere from 3 percent to 6 percent of the electorate, or roughly 500,000 voters. A 10 percent swing in those ballots would mean a net gain of 100,000 votes for the Republican candidate. Obama won Florida by 74,000 votes in 2012 and 236,000 in 2008.

We hopped on a plane, drove to the 4,869-home Kings Point community in western Broward, and marched into the Kings Point clubhouse. Residents on this particular morning had gathered around dozens of sign-up tables for clubs ranging from Current Events to Canasta and Ceramics.

"I don't like that they're trying to spread all this garbage about her emails, and donations to their foundation. It's not right, and it's not fair," said Shirley Rosen at the Hadassah table. "I'm all for her, and I don't think you'll find anyone around here who doesn't like Hillary, but there are very few Republicans. … Honestly, when someone tells me they're Republican I think to myself, 'I really don't know who you are.' "

Paula Layne, 80, was distributing cards for her funeral service business and bantering with friends, when she overheard a mention of Clinton.

"She's the smartest human being on Earth — truly. She's got good ideas, and she's not afraid of anybody. She's fearless. All my friends are Hillary people and very enthusiastic" Layne declared.

"If she were a man, we'd say she has brass ones," chimed in George Jaquith, another transplant from the Northeast. "And I think people are ready for a woman president. …"

"Not just a woman, but a smart woman," Layne cut in. "What she went through is an inspiration to all women. She overcame everything with such dignity and beauty and did not break up her family."

At the nearby Current Events Club table, Caroline Gore did not sound like much of a swing voter either.

"Any woman who votes for a Republican is an idiot, I'm going to tell you that right now. Look at the stricter abortion laws they're doing across the nation in a lot of places," she said. "It's not because she's a woman that I support her, but because of the issues. And I think she's the strongest candidate we have who can win the presidency and be a good president. I think she'd be a terrific president."

So it went throughout the Kings Point clubhouse. Enthusiasm for Clinton was almost unanimous. Almost.

"As much as I am a Democrat all my life, I don't know how much I like Hillary Clinton," said Viola Baras, 87, sitting at the Holocaust survivors table. "These emails? If most people did that, they would be in jail."

It turns out Mrs. Baras, who has two physician sons in the Tampa Bay area, was the source of the rumor of Clinton's weakness among Kings Point Democrats, though she doubted even the rare critic of Clinton in her circle would ever vote Republican.

"The Jewish vote will always be Democratic. As much as they may not like some of the policies with Israel, it doesn't affect their votes," said Baras, who survived the Auschwitz concentration camp.

• • •

Alan Bergstein, a Republican activist in Broward County, has spoken to countless Jewish groups in South Florida about why he thinks Republicans are better for Israel. These days he sounds about ready to throw in the towel.

Clinton will "absolutely" win a bigger share of Florida's Jewish vote than Obama did, Bergstein predicted, and almost nothing Republican political committees or billionaire conservatives like Sheldon Adelson do will change that.

National exit polls showed Obama received 69 percent of the Jewish vote in 2012, compared to 78 percent in 2008, although another, more detailed analysis of exit polls concluded he really received 74 percent in 2008. Considering that Obama's support among white voters overall dropped 4 percentage points, some experts see the drop in Jewish support as insignificant.

"It's terribly frustrating," said Bergstein, a former school principal in New York. "When I talk to people who are Jewish, like I am, and have made literally fortunes in their businesses and are extremely bright people, for them to not understand the situation tells me they are no longer Jews, they are Democrats first. Their religion has been superseded by their politics."

Polls show Jewish voters are more liberal on Middle East matters than most Americans, and Israel a lower-tier issue. Only 4 percent of Jewish voters cited Israel as the most important issue in their vote in a 2012 Public Religion Research Institute survey. More than half cited the economy, 15 percent said the growing gap between rich and poor, 10 percent said health care and 7 percent the deficit. They overwhelmingly supported abortion rights, same-sex marriage, environmental regulation, and more than half said they would pay more taxes to fund programs to help the poor.

"The position on Israel for most candidates is not going to be the determining factor for how Jews vote," said Ira Sheshkin, director of the Jewish Demography Project of the Sue and Leonard Miller Center for Contemporary Judaic Studies at the University of Miami. "Jews vote on social issues."

Wald, the UF professor and nationally recognized expert on Jewish voting behavior, dismisses the common supposition that Jews tend to be liberal due to Jewish values or historical experience. Only in America are Jews so concentrated on the left of the political spectrum, he noted, and Jewish support for Democrats has fluctuated at times.

"The political priority of most American Jews is making sure that the Jews continue to be full and equal participants in American life, and that is largely driven by their sense that the law should take no notice of religion," Wald said. "It's deeper than separation of church and state. It's more fundamentally that citizenship in the United States doesn't depend on your religion, your race, your ethnicity."

Jewish support for Democrats dropped in the 1960s, as the party embraced identity politics and policies such as affirmative action. President Jimmy Carter, who spoke often about being a born-again Christian, had little reservoir of goodwill with Jewish voters when he worked closely with Palestine Liberation Organization chairman Yasser Arafat. The Jewish vote shifted back toward the Democrats in the 1980s as the Christian right gained prominence in the GOP.

A 2007 Pew survey found Jewish voters more receptive than non-Jews to supporting a presidential candidate who was Catholic, Mormon, Muslim, atheist, black, woman, or Hispanic — but not Evangelical Christian.

"Every time the surveys come out showing that 58 percent of Republicans think the U.S. should officially be a Christian country, that just reminds Jews that their success here is never entirely secure," Wald said.

Times researcher Carolyn Edds contributed to this report.