Timothy D. Easley/AP Photo

Congressional Republicans were unimpressed by former Secretary of State Hillary Clinton's primetime interview with ABC News, knocking the perceived frontrunner for the 2016 Democratic presidential nomination and questioning her ability to serve as president.

Sen. Rand Paul, who also is considered a presidential contender, said Clinton's actions surrounding the Sept. 11, 2012 terrorist attacks in Benghazi, Libya, demonstrated that she is incapable of being commander in chief.

"Ultimately, that's a deal killer for her. I don't think she can win the presidency because, frankly, people want a commander in chief who can defend our troops and who will defend our embassies," Paul, R-Ky., said. "This wasn't a one-night thing. This was a six-months request for security that was denied."

During the interview with ABC News, Clinton hesitated to acknowledge that Libya was in the top 10 most dangerous countries for State Department employees, telling Diane Sawyer that Libya "would be in the top 25? but "there were places where we had much more concerns" that spread the State Department's resources for diplomatic security thin.

"How many countries are there more dangerous than Libya? Could be maybe five, six countries that dangerous, and you don't read the ambassador's cables?" Paul asked. "It's inexcusable. That was her 3 a.m. moment and she failed."

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House Speaker John Boehner, R-Ohio, said he also was "not satisfied" with Clinton's explanation in which she cited "systemic problems" at the State Department that she believed made it hard to know diplomatic security was inadequate in time to take action to prevent the deadly attack.

"If you're the secretary, you're responsible for the decisions that your department makes," Boehner said during a news conference today at the Capitol. "Simple as that."

As for Clinton's assertion that she and President Bill Clinton were "dead broke" when they left the White House, an apparent gaffe that forced Clinton to backtrack today, Paul invited Clinton to visit his state to get a first-hand look at how his constituents are struggling to make ends meet.

"Most people would think $8 million is a lot of money, and I think that [book deal] was signed while they were in the White House," Paul said. "There's a lot of Americans struggling. If she wants to come to eastern Kentucky, to my state, and see the miners who are out of work and the despair in their faces, and talk about her personal plight as being a poor spouse of the president, she's welcome to take that message around the country."

Today, Clinton worked to smooth over her remarks, telling "Good Morning America's" Robin Roberts that she and the former president owed $12 million in legal fees when they left the White House in January 2001.

"Now their net worth is between $100 to 200 million," Paul said. "The sad song of her reporting her personal financial difficulties - and the fact she hasn't driven herself in a car in 17 years - doesn't sound like she's going to connect well with the middle class."

Asked what he thinks of being identified as Clinton's favorite Republican, Sen. John McCain of Arizona joked, "I hope that doesn't get back to Arizona."

While Clinton mulls her next move, her supporters are working to defend her image ahead of a likely campaign for president.

"With all due respect, Senator Paul is an isolationist and Speaker Boehner can't manage his own caucus," Adrienne Watson, spokeswoman for Correct The Record by American Bridge, an organization that has been set up to defend Clinton, said in a statement. "No one should be taking advice from these two on diplomacy or leadership."