JERUSALEM - U.S. Sen. John McCain received a warm welcome during a brief visit to Israel aimed at burnishing his leadership credentials and courting Jewish voters for this fall's presidential election.

With his war hero status and a record of strong support for Israel, the presumptive Republican nominee is widely popular in the Jewish state. But some questioned whether uncritical support for Israel best serves Mideast peace efforts. McCain, who arrived Tuesday, is not scheduled to meet any Palestinian leaders during the two-day visit.

Officially, the Arizona senator was in Israel strictly on congressional business. The senior Republican on the Senate Armed Services Committee, McCain was being accompanied by two other senators: Joe Lieberman, an independent from Connecticut, who is Jewish; and Republican Lindsey Graham from South Carolina, two supporters who have been mentioned as potential running mates. Lieberman was the Democratic vice presidential candidate in the 2000 election.

Their weeklong international trip includes stops in Iraq, Jordan, Britain and France.

On arrival, McCain immediately headed to Israel's official Holocaust memorial, Yad Vashem. As his motorcade pulled up, dozens of tourists greeted him and chanted "Mac is back" as he shook their hands and posed for photographs.

During his 90-minute visit at the memorial and museum, McCain's eyes welled with tears as he viewed photographs from Nazi death camps. He laid a wreath in memory of the 6 million Jewish Holocaust victims and lit a memorial flame, wearing a skullcap placed on his head by Lieberman.

Signing the Yad Vashem visitors' book, he wrote: "I am deeply moved. Never again. John McCain."

McCain has said the visit is for fact-finding purposes and is not a campaign photo opportunity. But images of McCain embracing Israeli leaders and visiting Jewish holy sites could help McCain with Jewish voters, who make up crucial voting blocs in key states like Florida, New York and Michigan.

In an op-ed piece Tuesday in the Haaretz daily, the columnist Amir Oren wrote, "as far as Israel is concerned, and in view of the candidates' current positions - no one is better than McCain."

But Yossi Beilin, a dovish lawmaker and former peace negotiator, said a more hawkish candidate was not necessarily better for Israel.

"Some people think that to be a friend to Israel you have to be a Likudnik," he said, referring to the hardline Likud party. "A real friend is someone who will make an effort to bring an end to the Israeli-Palestinian conflict. The question is if McCain is that guy."

McCain was scheduled to meet Israeli Prime Minister Ehud Olmert and other Israeli leaders but had no plans to see any Palestinian leaders.

In Amman, Jordan, before traveling to Israel, McCain said he would make Israel-Palestinian peace efforts a top priority. "We will do whatever is necessary to assist that process so that we can bring about a peaceful settlement," he told reporters. He said that control of Gaza by the Islamic Hamas, which rejects the existence of Israel, is "not helpful."

Jonathan Sarna, an expert on American Jewish history at Brandeis University in Boston, said presidential candidates have a long history of visiting Israel ahead of elections. He said McCain's trip is unlikely to have a major effect on Jewish voters, who voted 3 to 1 for Democrats in recent presidential elections.

The visit is more likely to influence pro-Israel Christian evangelicals, he said, who make up a crucial part of the Republican base but have expressed distrust of McCain because of his moderate views.

"The big question, in terms of Jewish vote for McCain, is whether he can attain the kinds of numbers that Ronald Reagan reached in his prime - close to 39 percent of Jewish vote," he said. "Given that Jews reside in crucial swing states like Florida, even a smaller shift of Jewish votes from the Democrats to McCain could certainly affect the outcome of the election."

The Palestinians, for their part, claimed not to feel slighted by McCain's decision to meet only with Israeli leaders.

Palestinian negotiator Saeb Erekat said McCain had a "genuine commitment to peace" and would likely speak to Palestinian President Mahmoud Abbas during his visit. Abbas is conducting negotiations with Israel aimed at creating a Palestinian state alongside Israel.