WASHINGTON — A Republican group backed by the casino magnate Sheldon Adelson is starting a new effort in battleground states to win over Jewish voters who could be persuaded to turn away from President Obama and support Mitt Romney.
The group, the Republican Jewish Coalition, plans to begin a multimillion-dollar advertising campaign in the coming weeks called “My Buyer’s Remorse,” targeting voters in Florida, Ohio and Pennsylvania, aides said. The campaign uses testimonials from people who say they regret supporting Mr. Obama because of his economic policies and his posture toward Israel, in hopes of cutting into the wide advantage Democrats have held over Republicans among Jewish voters.
It is the latest foray into the election by Mr. Adelson, a staunch supporter of Israel who has vowed to spend as much as $100 million to defeat Mr. Obama. It marks an escalation of the partisan politics over Middle East policy and represents an emerging Republican strategy of highlighting voters who supported Mr. Obama four years ago but are now expressing disappointment, while signaling to others that they are not alone in shifting their allegiances.
Mr. Adelson and other members of the group’s board have pledged at least $6.5 million to build a comprehensive list of Jewish voters and to wage a word-of-mouth campaign, amplified through social media and television advertising.
The intensified pursuit of Jewish voters is coming into sharper view as Mr. Romney leaves on a trip that will take him to Israel this weekend. It is a closely watched visit, especially given the often-tense relations between Mr. Obama and Prime Minister Benjamin Netanyahu, who has known Mr. Romney for three decades.
Mr. Adelson has emerged as potentially the largest single donor in American politics this year. After initially backing Newt Gingrich in the Republican primary race, Mr. Adelson eased his skepticism of Mr. Romney, and his support has steadily grown.
In May, Mr. Adelson and Mr. Romney held a private meeting in Las Vegas, and aides said the two men have communicated occasionally since then. In June, Mr. Adelson and his wife each gave $5 million to a pro-Romney “super PAC.” His support for Israel aligns him with other influential Republican constituencies, including evangelical Christians, who see Mr. Obama as failing to support Israel sufficiently.
The fight for the Jewish vote is more of a hunt-and-peck search for disgruntled voters, considering that Mr. Obama won more than 70 percent of votes among Jews in 2008, according to exit polls. But with an estimated 600,000 Jewish voters in Florida, a critical swing state, Democratic leaders said they were not taking the constituency for granted, and they acknowledged a need to increase enthusiasm among Jews before November.
“They figure if they shave off a few points here and a few points there in the Jewish population through lying and distortions, they can win,” said Representative Debbie Wasserman Schultz of Florida, chairwoman of the Democratic National Committee. “But they can’t dress themselves up to be something appealing to the Jewish community when they aren’t.”
The Republican Jewish Coalition, the party’s leading outreach group for Jewish voters, has spent months developing a campaign to find like-minded voters in Florida, Ohio and Pennsylvania, the three swing states with the largest Jewish populations. It is the most extensive electoral effort undertaken by the group.
“We don’t need to get a majority of the vote to win,” said Matt Brooks, executive director of the Republican Jewish Coalition. “When we take votes away from Democrats, we are taking votes from a key part of their constituency.”
A Gallup poll of voters from June 1 to July 22 showed that Mr. Obama held a lead over Mr. Romney among Jewish voters of 67 percent to 25 percent. They said they strongly supported liberal issues that traditionally align with Democrats, including abortion rights, same-sex marriage and an overhaul of immigration laws.
But if Mr. Romney won 25 percent of the Jewish vote, it would be the best showing by a Republican candidate in more than two decades, which could be especially important in swing states, where the margin of victory could be narrow. Four years ago, Senator John McCain won about 21 percent of the Jewish vote.
The advertising campaign features a testimonial from Michael Goldstein, 48, a community college administrator from New Jersey, who said he enthusiastically supported Mr. Obama’s candidacy but became disillusioned by his administration. A lifelong Democrat, he said he was planning to support Mr. Romney by casting his first vote for a Republican in a presidential race.
“I was enamored with Obama,” Mr. Goldstein said in an interview. “I thought he was sharp, intelligent and brought a new sense of wonder to politics. The fact that we were helping elect the first African-American president of the United States made me very proud, but I don’t believe anything he says anymore. I go more by his actions than by what he says.”
Mr. Goldstein said he gradually became disenchanted with Mr. Obama when his promises to change Washington did not come to pass. He said he was particularly incensed by the administration’s stance toward Israel, particularly the president’s view that the 1967 borders should be a starting point for negotiations for a two-state peace solution. He said he also believed that Mr. Obama showed disrespect to Mr. Netanyahu.
It remains an open question how many voters share the views of Mr. Goldstein, who conceded that some of his frustrations at Mr. Obama were also a result of what he saw as the president’s failure to uphold liberal principles on gun control and some social issues. But he said that his discontent was strong enough that he would cast a vote for Mr. Romney and that he intended to campaign aggressively in Pennsylvania.
“It doesn’t take a lot of buyer’s remorse to potentially shift the outcome,” said Ari Fleischer, a member of the Republican Jewish Coalition’s board and a former press secretary to President George W. Bush.
While the Obama campaign and the Democratic Party have increased their outreach, leaders of several Jewish organizations dismissed the possibility that the Republicans could make significant inroads in the November election.
“There is a very large chunk of the Jewish community that is very Democratic that can’t be eaten into,” said Mik Moore, founder of the Jewish Council for Education and Research. “There is a fight for maybe 10-15 percent, but nobody is underestimating the impact that the massive independent spending can have on the campaign.”
Jeremy Ben-Ami, the president of J Street, a Jewish lobbying group in Washington that favors Democratic candidates, said the effort by Mr. Adelson and the Republican Jewish Coalition would fall short.
“Every single number indicates there is simply no such thing as a Jewish problem for the president,” Mr. Ben-Ami said. “The people who vote only on Israel didn’t vote for Obama last time and know who they are voting for already.
