Obama promised answers. "If four Americans get killed, it's not optimal," the president said Thursday during an appearance on "The Daily Show" on Comedy Central. "We're going to fix it."
Republican presidential candidate Mitt Romney has been criticizing the administration for initially describing the attack as a spontaneous mob reaction to an anti-Muslim video on YouTube when they now acknowledge it was a terrorist attack. U.S. officials told The Associated Press that the CIA station chief in Libya reported to Washington within 24 hours of the attack to say there was evidence it was carried out by militants, although it's unclear who received that information right away.
Ryan told "The Charlie Sykes Show" on Milwaukee radio station WTMJ that Obama's "response has been inconsistent, it's been misleading."
"Why the stonewalling?" the Wisconsin congressman asked.
"The thing about Benghazi is that they continue shifting their story," he said in a second Wisconsin radio interview on the Jerry Bader Show on Green Bay's WTAQ. "And they're refusing to answer the basic questions about what happened. Why blame (a) YouTube video for two weeks after knowing that that wasn't the case? It leads to more questions than answers."
The Wisconsin congressman said he hopes a congressional investigation and Monday night's presidential debate, which will focus on foreign policy, will provide answers.
"That's why you have these investigations in Congress, to find out what exactly happened and why the stonewalling and why blaming (the) YouTube video for two weeks," he said. "The reason we need to get to the bottom of this is so we can prevent something like this from happening again."
Ryan and Romney have been using the death of U.S. Ambassador Chris Stevens and three other Americans on the 11th anniversary of the Sept. 11 attacks to criticize Obama's overall foreign policy record.
"The Benghazi thing would be a tragedy in and of itself if it was an isolated incident," Ryan said on WTMJ. "The problem is it's not simply an isolated incident but a picture of a broader story of the absolute unraveling of the Obama administration's foreign policy. Go around the world and you see policy failure after policy failure, and that is something that they just can't defend."
Obama insisted information was shared with the American people as it came in. The attack is under investigation, Obama said, and "the picture eventually gets filled in."
"What happens, during the course of a presidency, is that the government is a big operation and any given time something screws up," Obama said on "The Daily Show." ''And you make sure that you find out what's broken and you fix it."
Asked if the White House had become aware of the CIA cable and when, spokesman Tommy Vietor declined comment "on what, if true, would be an internal and classified CIA cable."
Obama did not mention the attacks during a raucous rally at George Mason University in Washington's northern Virginia suburbs. Instead, the president debuted a new routine riffing on the "you might be a redneck" stylings of comedian Jeff Foxworthy to poke at Romney.
Obama's version warned how "you might have Romnesia," characterized by shifting positions on a variety of issues. "Here's the good news," the president said with a smile, "Obamacare covers pre-existing conditions."
Romney was headed to Daytona Beach, Fla., for a Friday night rally with Ryan. The GOP nominee made a play for moderate voters in a new ad that featured video of him at the first presidential debate talking about how he would bring the political parties together to help the economy.
While they were focused on southern battlegrounds, NBC News/Wall Street Journal/Marist polls released Thursday showed Obama retaining his lead over Romney in Iowa and Wisconsin, two Midwestern battlegrounds. Obama's campaign circulated a memo highlighting the president's strength during the early voting period in Ohio, where Romney has largely staked his hopes of winning the White House.
But both were keeping relatively light public schedules before a weekend devoted to preparing for their third and final presidential debate, set for Monday in Boca Raton, Fla. After the event in Virginia, Obama was heading for the Camp David presidential retreat in Maryland to prepare; Romney planned preparations in Delray Beach, Fla.
Meanwhile, Libertarian candidate Gary Johnson filed a lawsuit in U.S. District Court in Washington against the Commission on Presidential Debates for excluding him from the debates.
Associated Press writer Frederic Frommer contributed to this report.