“We can and we will get it under 6 percent,” Biden said, without giving a timeframe to get the figure below the 7.8 percent seen last month.

Ryan, Republican Mitt Romney’s running mate, said that the “entire premise” of their economic plans was to achieve such a goal.

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While unemployment in September unexpectedly fell to 7.8 percent, the lowest level since Obama took office in January 2009, only one president — Ronald Reagan — has been re-elected since World War II with unemployment above 6 percent.

Moderator Martha Raddatz of ABC News turned to domestic issues after the two candidates attacked each other on foreign policy at the start of the 90-minute debate at Centre College in Danville, Kentucky.

“What we are watching on our TV screens is the unraveling of the Obama foreign policy,” Ryan said. He criticized the Obama administration for a lack of security in Libya before the Sept. 11 attack on the consulate in Benghazi that killed four Americans, including Ambassador Chris Stevens, and for the original statement that the attack was part of a protest.

Biden, 69, said whatever mistakes had been made in the original assessment of the attack “will not be made again,” and went after Romney and Ryan, 42, for not having a clear vision on foreign policy.

‘A Bunch of Malarkey’

Biden also said, “With all due respect, that’s a bunch of malarkey,” in response to Ryan’s criticism of the Obama administration’s handling of the Benghazi attack and his charge that the president is advocating “devastating” defense cuts.

Thursday night’s showdown took on greater significance after a majority of voters said Obama lost to Romney, a former Massachusetts governor, in their first debate on Oct. 3. Romney has gained in national and state polls since then.

The two presidential candidates will meet in two more debates later this month.

Biden and Ryan also squared off on the issue of Iran, with Ryan saying the Obama administration hasn’t done enough to ensure the country won’t get a nuclear weapon.

“It’s because this administration has no credibility on this issue, it’s because this administration watered down sanctions,” Ryan said. “They say the military option is on the table, but it’s not being viewed as credible.”

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Go to War?

Biden shot back, saying, “Incredible,” with a laugh.

“This is a bunch of stuff,” he said of Ryan’s criticism. He also said the sanctions on Iran are “crippling” and said war should always be “the last resort.”

“What, are you — you’re going to go to war? Is that what you want to do?” Biden said to Ryan.

“We want to prevent war,” Ryan responded.

Biden accused Romney and Ryan of failing to protect the middle class, saying they were focused on lowering tax rates for the highest earners and were out to weaken Medicare.

“They haven’t put a credible solution on the table,” Ryan said of Medicare. Mentioning plans for a voucher system for the program is the Democrats’ way to “scare people,” he said.

Common Enemy

Before the vice presidential debate, supporters of both candidates said the two would face a common enemy: their own words.

Biden’s task will be to limit his loquaciousness and avoid quips that might undermine administration positions, while Ryan must defend the two government spending plans he wrote as chairman of the House Budget Committee, their backers said.

“Joe’s challenge is to avoid saying something before he thinks about it,” said former Colorado Senator Gary Hart, who debated with Biden when both sought the 1988 Democratic presidential nomination. “He has to do a little editing as he goes along.”

For Ryan, the test will be how he defends the “Medicare issue,” as presented in the two budgets he shepherded through the House, said the chamber’s former speaker, Republican Dennis Hastert of Illinois. “Biden will take cheap shots on the budget and Paul will have to be prepared to come back at him.”

Ryan’s budget for this fiscal year, passed by the U.S. House 228-191 in March, called for changes in Medicare and cut food stamps, Pell grants for college students and other programs for the poor. It included $5.3 trillion in spending cuts over 10 years, increases in defense spending and lower tax rates for higher earners.

Final Preparations

Both candidates took several days off from campaigning to get ready for the debate. Thursday, they made last-minute preparations and got a look at the stage.

“I am looking forward to it,” Biden told reporters in New Castle, Delaware, before boarding Air Force Two for the flight to Danville. Obama called his vice president from his own Air Force One flight to Florida to wish him luck.

Ryan spent the day at a Danville-area hotel, reading briefing binders, exercising and spending time with his family before surveying the debate site. He also took to the social networking site Twitter to signal he was ready for the face-off.

“Let’s get this done!” he said in a message posted on the site, along with a picture, apparently taken while he visited the debate stage, of him grinning as he sat at the table where he will face Biden.

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