For the latest installment, Couric asked the contenders: "What makes you the candidate best able to fix an ailing economy?"
Also, check out the candidates' full responses to the previous questions in our "Primary Questions" video library.
Couric: In our latest poll, 38 percent of Americans say the economy and jobs, they describe that as the most important issue. What makes you better qualified to handle a struggling economy?
Clinton: Well, I've been talking about what we need to do with the economy now for my entire campaign. You know, about a year ago, I said we had to start dealing with this mortgage crisis or we were going to really see the deterioration that unfortunately has happened in the economy.
I would still like to see us have a moratorium on home foreclosures. Let's help people stay in their homes. We need to freeze these interest rates. Otherwise, we're going to lose millions of more people out of their homes.
And I think it's very important that we start generating new jobs. This administration hasn't done a very good job of that. That's why I want to put money into green collar jobs and start putting people to work weatherizing homes and installing solar panels.
You know, there's a lot that I would do starting day one. And I think that, you know, the lessons I learned from the first Clinton administration about how to be a good steward of the economy, I will bring with me into the White House as we look towards the future, so we get this economy working for everybody again.
Couric: In our new CBS News poll, 38 percent of Americans say the economy and jobs, they describe those as the most important issue. Why are you best able to fix an ailing economy?
Huckabee: I was the first person to recognize the economy was in trouble. I got laughed at it by my other Republican colleagues for suggesting that our economy was going south. Truth is I was seeing it before they were because I understood from a governor's perspective and also from growing up - sort of at the bottom of the economy, not the top, that when people are paying more for fuel and healthcare and education it affects folks who drive trucks and who are working on the factory floors and teaching school a whole lot quicker than it affects folks who are at the top of the economy who don't feel the pinch quite as quickly.
But also being a governor. I've steered the canoe through low water and high water. I've taken a deficit and turned it into a surplus. I've led in the creation of jobs. I understand that if you really wanna create jobs you have to produce something, which means you gotta change the tax system so Americans are producing things and actually making things again. That is an important part of having a strong, healthy economy and building the middle class.
Couric: Thirty-eight percent of respondents in our new CBS News poll said the economy and jobs, they said those were the most important issues facing this country. Why do you think you're in the best position to fix an ailing economy?
Romney: I think people recognize that … to understand the economy, fundamentally, you have to have had a job in the private sector. You … had to have a job where you see jobs come and go. I've done business around the world in over 20 different countries.
I've helped turn around businesses in trouble. I also, as you know, took over the Olympics, when they were in trouble, and helped to get them back on track. In Massachusetts, our state was in a ditch; was going downhill fast, losing money every month and losing jobs every month. It was hard. But we were able, Republicans and Democrats, to work together, to turn that around.
We didn't raise taxes. We rebuilt our economy. And it … continues to come out of … the deep trough it was in. So I believe my record of actually turning things around is quite distinctly different from that of Sen. McCain. He's been, you know, he's been in the Senate for the last 25 years. You gotta have a record, I think, to show that you're able … to actually manage an economy.
Couric: In our new CBS News poll, Senator, 38 percent of respondents said the economy and jobs, they cited that as the most important issue facing this country. Why do you think you're best qualified … to help a struggling economy?
McCain: Well, I think because I've been involved in the major economic issues going back to the Reagan revolution when we cut taxes and restrained spending. And put this country back on the path to prosperity. At the time he became president we had ten percent unemployment and 20 percent interest rates.
And we cut taxes. But we restrained spending and the growth of government. And I've been involved in the restrain of spending. I'm called the sheriff … by some of the appropriators. And, by the way, that's I'm not most popular with some of my colleagues in the Senate when I take on their pork barrel projects.
So I've been involved in the major economic issues of the day. I have people who are advising me, like Jack Kemp, and Phil Graham, and so many other noted, economists and conservatives like Senator Tom Coburn. I have the experience and knowledge on economic issues the lead this country based on fundamental conservative economic principles.
Couric: In fact, Sen. Obama, according to our latest poll, 38 percent of Americans say the economy is the most important issue facing this country. Why do you think you're best qualified of all the candidates to handle a struggling economy?
Obama: Well, a couple of reasons. No. 1, I think we've been ahead of the curve. I'll just give you an example on the economic stimulus package that has been needed, you know? The agreement that's been negotiated by President Bush in Congress largely follows the contours of something we put up very early, which says let's get tax rebates into the pockets of Americans quickly.
Let's extend unemployment insurance so that the jobless that are more likely to be long-term unemployed at twice the rate of the previous recession that they're getting some relief. I've shown I think the judgment to anticipate some of the problems that we've had.
More importantly, I've spent 20 years, Katie, trying to make sure that our economy is prospering from the bottom up and not just the top down. And so my economic program that includes tax cuts for the middle class, $1,000 per family to offset the payroll tax, relief for seniors who don't make a lot of money so they don't have to pay income tax, providing additional tax breaks for homeowners on their interest rates.
All those things are designed to strengthen the purchasing power of the middle class, strengthen the economy. And if you combine it with my plan to improve education and to have a sensible energy policy that invests in clean energy - like solar and wind and biodiesel - I think that's the package that will move us forward in the right direction.