ST. PAUL, Minn. —  The two vice-presidential candidates led the way Wednesday as the Obama and McCain campaigns worked to draw clear battle lines on Iran and Israel.In a highly anticipated speech at the Republican convention, Alaska Gov. and GOP vice presidential nominee Sarah Palin mocked Sen. Barack Obama (D-Ill) for saying over a year ago that he would meet the leaders of pariah states unconditionally. "Terrorist states are seeking nuclear weapons without delay — he wants to meet them without preconditions," she said, during her acceptance speech Wednesday night at the Xcel Energy Center in St. Paul.

Palin’s address followed a speech by former New York Mayor Rudolph Giuliani — the most popular candidate among Jewish GOPers in the primaries — in which he warmed up the crowd with his own swipes at Obama, including an assertion that the Democratic nominee had flip-flopped on the issue of Jerusalem. "When speaking to a pro-Israeli group, Obama favored an undivided Jerusalem, like I favor and John McCain favors it," Giuliani said. "Well he favored an undivided Jerusalem — don’t get excited — until one day later when he changed his mind."

Earlier in the day, the Democrats launched their own Middle East-related attack, as Obama’s running mate, Sen. Joe Biden (D-Del.), used a 20-minute conference call with members of the Jewish media to blast the Bush administration and Sen. John McCain (R-Ariz.). The Democratic vice presidential candidate blamed the Bush administration’s sluggish diplomatic efforts for slowing up Israeli-Palestinian talks and paving the way for the ascendancy of Iran and its proxies, Hamas and Hezbollah. Biden also argued that the administration has failed to respect Israel’s autonomy, citing for example reports that at a certain point the White House was directing Israel not to engage in talks with Syria — and he appeared to reject the administration’s reported efforts to block Israel from taking military action against Iran.

"This is not a question for us to tell the Israelis what they can and cannot do," said the Democratic vice presidential candidate. "I have faith in the democracy of Israel. They will arrive at the right decision that they view as being in their own interests." That said, Biden added, the Bush administration could have done much more on the diplomatic front to help avert the potential need for military action.

Taken together, Biden’s press call and the GOP convention speeches underscored the ramped up efforts by both campaigns to paint the other side as promoting a reckless foreign policy that would endanger Israel and undermine U.S. interests. They come as polls suggest Obama commands about 60 percent of the Jewish vote — a solid majority, but at least 15 points less than the percentages recorded by recent Democratic presidential candidates.

Even as both sides attempted to draw stark distinctions on the Israeli-Palestinian crisis, it was unclear if any exist. While it is true that Obama felt the need to clarify comments he made on Jerusalem’s future to thousands of pro-Israel activists in June, both he and McCain have expressed essentially the same view — that they share Israel’s concerns on the issue and view it as a matter to be ultimately decided by the two sides in negotiations. And, though for years the Bush administration was reluctant to dive into Israeli-Palestinian negotiations, McCain has pledged to do so. Both Obama and McCain favor a two-state solution, place most of the blame on the Palestinians for the failure to reach one, back efforts to isolate Hamas and shore up Palestinian Authority President Mahmoud Abbas.

On Iran, however, the disagreements appear more pronounced — both between Obama and the Bush administration, and between the two presidential campaigns.

In mocking Obama’s stated willingness to meet with the president of Iran, Palin was echoing a longstanding line of attack against Obama, employed not only by Republicans, but by Obama’s main rival in the Democratic primaries, Sen. Hillary Clinton (D-N.Y.). Since Obama first made the remark, during a primary debate more than a year ago, he appears to have backtracked, saying he would require extensive preparations before such a meeting.

Still, Obama and Biden have stuck to the view that hard-nosed talks between the United States and Iran could ultimately lead Tehran to change its behavior — and, failing that, make it easier to build international support for tougher sanctions and possible military action against the Islamic regime. McCain, on the other hand, has scoffed at the notion that talking with top Iranian leaders would do any good. At the same time, McCain has opposed several congressional measures backed by Obama that supporters say would place increased economic pressure on Iran to abandon its nuclear pursuits.

Biden argued during his conference call that the net result of McCain’s positions is that he’s offering a choice between "unacceptable status quo or war."

"There’s nothing in between with the McCain doctrine — nothing," Biden said. "That is no option. That is a Hobson’s choice."

In her speech Wednesday night, Palin expanded the Iran debate, arguing that the energy policies she favors — in particular, expanding oil drilling in the United States, and especially Alaska — would help diminish the Iranian threat.

"To confront the threat that Iran might seek to cut off nearly a fifth of world energy supplies or that terrorists might strike again at the Abqaiq facility in Saudi Arabia or that Venezuela might shut off its oil deliveries," Palin said, "we Americans need to produce more of our own oil and gas."

(Ami Eden contributed in New York to this report.)