CHILLICOTHE, Ohio -- Former President Bill Clinton added some meat to his argument that President Barack Obama needs another four years to fix the economy on Thursday night, citing work by an economist whose book is often cited by Republicans talking about the national debt.

Clinton, at his third event of the day in Ohio, after a morning stop in Wisconsin, spoke to a crowd of 2,000 for about 45 minutes, even though he began his remarks with his voice sounding on the verge of failing. "I've almost lost my voice in the service of my president," Clinton said.

The 66-year old former president seemed to gain strength as he spoke. And around halfway through his remarks, he got the crowd's attention with this comment: "The whole election may come down to this, this one thing."

"I know that no one who ever served as president -- not me, not Franklin Roosevelt, not anyone -- could have repaired all the economic damge done during that crash in four years," Clinton said.

And then he cited a book called This Time It's Different: Eight Centuries of Financial Folly, by Kenneth Rogoff and Carmen Reinhart.

This book has become a reference point for many concerned about the nation's $16 trillion debt. Rogoff and Reinhart wrote that history has shown that once a nation's debt swells to 90 percent of the gross domestic product, it takes a percentage point off of that nation's economic growth per year.

Essentially, as they said in a column a year ago, "too much debt means the economy can't grow."

The $16 trillion in U.S. debt is about equal to the total U.S. economy, though Rogoff and Reinhart's precise metric was debt held by the public. That figure is about $11.3 trillion and does not include the $4.8 trillion in intra-governmental debt, which refers to money owed by the treasury to government accounts, such as the Social Security trust fund.

Clinton said Rogoff is a moderate Republican. And then he related a conversation he had with Rogoff after reading his book.

"I called him on the phone and I said, 'I read this very carefully. I just have a question. Do you believe that there's any way America could have fully recovered from that crash in four years?'" Clinton said. "He said, 'Lord no.'"

"He said, 'No serious person believes that.' He said, 'The average country takes 10 years,'" Clinton said.

Clinton did not mention that Rogoff and Reinhart wrote a column for Bloomberg News two weeks ago, arguing that the economic crisis of 2008 and 2009 was not a "borderline" economic crisis, but rather a "full-blown systemic meltdown."

History has shown that economies hit by a systemic event have taken an average of about 10 years to recover, the two scholars wrote. Their point was to counter those, including Republican Mitt Romney, who have said that Obama's policies have made the economic downturn worse by prolonging it and stifling recovery. Romney's point, made by many others as well, has been that the U.S. economy usually recovers from a crisis within a few years.

"The most recent U.S. crisis appears to fit the more general pattern of a recovery from severe financial crisis that is more protracted than with a normal recession or milder forms of financial distress," Rogoff and Reinhart wrote. "There is certainly little evidence to suggest that this time was worse. Indeed, if one compares U.S. output per capita and employment performance with those of other countries that suffered systemic financial crises in 2007-08, the U.S. performance is better than average."

Clinton, who has boasted about the amount of news and economic data he consumes each day, likely was aware of this column, even if he did not reference it.

Clinton said that at the end of his conversation with Rogoff, he asked him, "Can we beat the global average of 10 years?"

"He said, 'You bet we can. … But we have to do the right things,'" Clinton said. "President Obama wants to do the right things in the next four years."

Clinton also let fly a memorable line when talking about Romney's campaign ad that talks about Chrysler building Jeeps in China. The ad has been scathingly criticized by much of the Ohio press for being misleading, and Clinton said the Romney campaign had been "caught with their hand in the cookie jar."

Clinton offered this advice: "When you get caught with your hand in the cookie jar, you kind of shrug your shoulders and take it out."

The Romney campaign instead increased its advertising, he said, and "doubled down on something that the people involved proved is false."

Also on HuffPost:

Loading Slideshow...
  • Prosecution For Financial Fraud Hit A 20-Year Low During The Obama Administration

    Despite Obama's <a href="" target="_hplink">promises to crack down</a> on Wall Street, federal prosecutions of financial fraud hit a 20-year low last year, according to a <a href="" target="_hplink">November study from a watchdog group</a>. The number of these types of prosecutions has been falling every year since 1999 -- in other words, there were more prosecutions during every year of George W. Bush's presidency than during every year of Obama's.

  • Income Inequality Is Worse Under Obama Than Under Bush

    The rich took home a <a href="" target="_hplink">greater share of America's income pie</a> from 2009 to 2010 than they did between 2002 and 2007, according to an April analysis from Emmanuel Saez, a professor at the University of California, Berkeley. That means the gap between the rich and the poor was more pronounced under Obama's presidency than under George W. Bush's.

  • Obama Wants To Lower The Corporate Tax Rate

    Some of America's most profitable companies used a variety of loopholes to pay <a href="" target="_hplink">less than zero in taxes</a> between 2008 and 2010, according to a November 2011 report by the Citizens for Tax Justice. But the Obama administration wants to make it even easier for corporations to have a smaller tax bill; Obama proposed a tax overhaul that would <a href="" target="_hplink">cut the corporate tax rate</a> from 35 percent to 28 percent.

  • Health Care Reform Won't Make Health Care Cheaper For Most Americans

    Once the health care law takes effect, insurance companies will be footing the bill for millions of previously uninsured Americans and for those who were denied coverage for pre-existing conditions. And health insurance companies will <a href="" target="_hplink">likely pass on to consumers the cost</a> of insuring the new patients. After Massachusetts enacted a similar health care plan in 2006, premiums for an individual plan in the state <a href="" target="_hplink">rose 18 percent</a> over three years.

  • Obama's Housing Programs Have Largely Been A Failure

    In 2009, Obama announced the Home Affordable Mortgage Program, promising to help 3 to 4 million borrowers, but as of January -- more than three years into the program -- HAMP had <a href="" target="_hplink">only reached 1 million borrowers</a>. In an aim to give the program legs, administration <a href="" target="_hplink">officials changed the rules</a> in January to make more borrowers eligible. Still, the fixes were likely too little too late, experts said at the time.

  • Homeowners Haven't Seen Much Out Of That Huge Mortgage Deal

    The Obama Administration touted the $25 billion mortgage deal it reached with 49 states and the big banks to settle allegations that banks mishandled mortgages. As part of the settlement, banks said they would <a href="" target="_hplink">offer at least $10 billion</a> in loan forgiveness to homeowners. But months after the deal was inked, <a href="" target="_hplink">banks have been slow</a> to hand out the money.

  • Democrats Have Received Lots Of Campaign Cash From Bain Employees

    The Democratic National Convention will feature <a href="" target="_hplink">employees of firms run by Bain Capital</a> -- the private equity firm where Mitt Romney was formerly CEO -- likely in an aim to raise questions about Romney's tenure at the now-controversial company. But Democratic candidates and committees had <a href="" target="_hplink">actually netted double the amount of campaign cash from Bain workers</a> as of May than their Republican counterparts since 2008, according to the <em>Boston Globe</em>. Now, Republicans are beating their Democratic colleagues in Bain cash, with <a href="" target="_hplink">58 percent of donations from Bain</a> employees going to Republican candidates and parties, according to the Center for Responsive Politics. <strong>CORRECTION:</strong><em> An earlier version of this slide misstated that Democrats were receiving more donations from Bain employees than Republicans. That was the case in May. As of September Republicans are receiving more donations from Bain employees.</em>

  • Goldman And Other Wall St. Firms Have Largely Escaped Punishment For Their Role In The Financial Crisis

    The announcement last month that the Justice Department wouldn't be prosecuting Goldman Sachs over allegations surrounding the financial crisis was <a href="" target="_hplink">a reminder for many</a> that the Obama Administration has largely let banks off the hook for their role in the meltdown. And regulators and officials may be running out of time; <a href="" target="_hplink">the statute of limitations</a> for crimes related to the financial crisis is fast approaching, according to <em>The New York Times</em>.

  • The Revolving Door Is Alive And Well In Obama Administration

    Many current and former members of the Obama Administration have ties to Wall Street. The <a href="" target="_hplink">list includes</a> the president's current and former chiefs of staff -- Jacob Lew and Bill Daley, respectively -- as well as his former budget director, Peter Orszag, and others.

  • Too Big To Fail Banks Have Grown Under Obama

    At the end of 2011, five big banks, including Bank of America and JPMorgan Chase, held <a href="" target="_hplink">56 percent of the U.S. economy</a>, according to Bloomberg, compared to 43 percent five years earlier. That's right, the too-big-to-fail banks have actually gotten bigger.

  • The U.S. Has Gained A Lot Of Low-Wage Jobs During The Recovery

    Welcome to the U.S. of Low-Wage America. Most of the jobs lost during the recession paid middle wages, while most of those <a href="" target="_hplink">gained during the recovery were low-wage jobs</a>, according to a recent study from the National Employment Law Project.

  • Incomes Declined More During The Recovery Than The Recession

    Median <a href="" target="_hplink">household income fell 6.7 percent</a> between June 2009, when the recession technically ended, and June 2011, according to a Census Bureau study cited by <em>The New York Times</em>. That's more than the 3.2 percent incomes fell during the recession, between 2007 and 2009.

  • Payroll Tax Cut May Expire On Obama's Watch

    Last December, congressional Democrats managed to save the payroll tax cut for one more year, giving 122 million workers a few extra bucks each paycheck, but now that <a href="" target="_hplink">boost may quietly disappear</a>, according to the <em>Wall Street Journal</em>. That's because the White House won't be pushing for another payroll tax cut extension this year.

  • Many Top Obama Donors Are Employees Of Major Corporations

    Of the top 10 companies with employees donating money to Obama's campaign, three are big banks: JPMorgan Chase, Citigroup and Goldman Sachs, according to <a href="" target="_hplink">the Center for Responsive Politics</a>. Some of Obama's other major contributors include employees from big companies such as Microsoft and Google.