ALISON STEWART, PBS NEWSHOUR ANCHOR: And Judy Woodruff is in Iowa capital of Des Moines and joins me now for more on caucuses.

Judy, when you do the math, you realize there's only 30 delegates at stake for the Republicans, 44 for Democrats. In the giant big picture, that's about 1 percent of all the delegates.

So, this really isn't about the math, is it? This is really about something bigger.

JUDY WOODRUFF, PBS NEWSHOUR ANCHOR: It's not about the numbers. It's about that Iowa is first. It's the reason that probably the entire political press corps in the United States, which is usually somewhere between Washington and New York, is now in the state of Iowa.

It's because the results in Iowa catapult the winner and also the person who second, even third, on to the next contest, in New Hampshire, and then beyond that to South Carolina and Nevada. But it's all about who came out of the first state where they went door to door, appealing directly to voters — who did the best job of connecting.

ALISON STEWART: The Republicans are focusing clearly on differentiating themselves from the Obama administration's legacy, policy, health reform, immigration. Ted Cruz at the forefront of this. I know you went to one of his rallies. How is that message landing?

JUDY WOODRUFF: I did go to one of the Ted Cruz rallies today in Ames. It was an overflow crowd in the convention kind of meeting room there. Very enthusiastic for Ted Cruz. His supporters are hard-core conservatives who absolutely love the message, the anti-Obama message, down the line.

But the question for Cruz is whether the Donald Trump phenomenon, which has absolutely upended this race, is going to overcome the organization and the anti-Obama message of Ted Cruz. And, frankly, the fact that there are just still so many candidates in the race, more than a dozen Republicans are running.

ALISON STEWART: Well, when we talk about how the Democrats are positioning themselves, they're obviously both vying for Obama supporters. Hillary Clinton presenting herself as heir in some ways. Senator Bernie Sanders saying, hey, I think we should go farther on health reform. I think we should go after Wall Street.

How is that playing out?

JUDY WOODRUFF: Well, it is a huge battle between Clinton and Sanders. Hillary Clinton came into Iowa, and people presumed she was going to walk away with this because of her pedigree, her resume. It hasn't been that at all.

Bernie Sanders has run a very tough race here right now. It's competitive. He has young people in the state are supporting him by enormous margins.

She, on the other hand, has worked the state very hard. She learned some lessons from 2008 when she thought she was doing well and lost to Barack Obama.

It is, Alison, about who can carry on the Obama legacy, but as you said, it's also, in Bernie Sanders' case, it's about who can do more with it than what President Obama has done? Who can do an even better job of bringing health care to all Americans? Bernie Sanders talks about single-payer health care and so on down the list, whether it's going after Wall Street or some of these other issues that are important to liberals.

ALISON STEWART: And before we let you go, former Secretary of State Clinton won the endorsement of "The New York Times," as well as "The Des Moines Register" there in Iowa.

What else does "The Register" have planned today?

JUDY WOODRUFF: They are going to hold a news conference after this program is off the air, announcing the last poll before the caucuses. Historically, "The Des Moines Register" has done better than anybody else forecasting the outcome. Their pollster, Ann Selzer, famously predicted Barack Obama was going to win the caucuses in 2008, when most others were predicting something different.

So, a lot of people are paying attention. It's so big that "The Des Moines Register" is having a news conference to announce this poll when it comes out tonight.

ALISON STEWART: Judy Woodruff, thank you so much.

JUDY WOODRUFF: Great to talk to you.