CNN's latest Iowa poll: Live analysis on Buttigieg surging to first place

Our new CNN/Des Moines Register/Mediacom poll of likely Iowa Democratic caucusgoers shows that Buttigieg has climbed to 25%. He was at 9% in September.

Buttigieg is 9 points ahead of Warren. She's at 16%, down from 22% in September. Biden's at 15%, down from 20% in September. Sanders is also at 15%, up from 11% in September.

Klobuchar rounds out the top 5 at 6%, her highest level of support in any of CNN's Iowa polls.

Everyone else is below 5%.

Here are a few other takeaways from the poll:

If there is one lesson you should take from the dramatic shifts in our Iowa polls over the last two months, it's that things are volatile.

Although a higher percentage of caucusgoers say their mind is made up (30%) now than in September (20%), 69% say they either don't have a first choice or could be persuaded to vote a different way.

There are seven candidates with favorable ratings over 50%.

When you look to history, leaders in Buttigieg's position have lost many times. In caucuses without an incumbent running, the leader in the Iowa polls at this point have only gone on to win the caucuses three of the last nine times since 2000. That means they have lost more often than they have won.

This is especially the case when the leader was polling below 49% like Buttigieg is currently. In each of these six cases, the Iowa polling leader at this point since 2000 went on to lose the caucuses -- and they went on to lose the nomination as well.

Now, that doesn't mean Buttigieg is destined to lose or anything like that. Rather, it's an indication that a lead at this point doesn't necessarily mean a whole lot when there are a slew of well-liked candidates not too far behind.

Klobuchar was one of the candidates that analysts such as myself thought might catch fire with the Iowa electorate. She's from next door Minnesota, is a woman (a cycle after Democrats nominated them in record numbers) and has electability bonafides that no other Democrat in the race has.

In this poll, her horserace standing (6%) is her best in any Iowa poll done by us this cycle. Her very favorable rating of 20% is also her highest to date.

The continuing decline for Biden and rise of Buttigieg does seem indicate that there is a lane for a more moderate alternative. With Buttigieg sure to be attacked over the months to come, Klobuchar might just be able to squeeze in there as that candidate.

Yet Klobuchar's path is much more complex than Buttigieg's was in September when he was at 9%. Buttigieg's very favorable rating was 33% in September compared to Klobuchar's 20% now. A majority (55%) said they were at least actively considering caucusing for Buttigieg in September. Only 39% say the same of Klobuchar now.

But those numbers are at least malleable. Buttigieg's very favorable ratings rose by nine points over the last two months, for example.

Klobuchar can now say she is a top five candidate in Iowa (though she still falls 9% below the two candidates above her, Biden and Sanders). With over two months to go, there are a number of historical examples of candidates gaining the ground Klobuchar needs in order to become a top tier candidate.

Sanders stands at 15% in our latest poll, which is up slightly from 11% in September. He now basically equals the 16% that he had in June.

When you dig in a little deeper, you can see some more positive signs for him. His very favorable rating is up 5 points from 26% in September to 31% now. That's 7 points ahead of Biden's 24%.

In the horserace in particular, you see that many of Sanders' gains seem to have come at the expense of Warren.

Sanders now stands at 34% among very liberal caucusgoers. Warren's at 32%. In September, it was Warren 48% to Sanders' 20% with this same group. That's a 30-point change in the margin between the two of them.

Perhaps not surprisingly, Sanders is also doing considerably better among those who caucused for him in 2016. He's now at 39% with them, while Warren is at 22% with them. In September, it was Warren's 32% to Sanders' 25%. That's a 24-point shift in the margin between the two of them.

Will Sanders be able to gain more ground next poll? It's possible, but there are two big flashing orange lights: a majority of caucusgoers (53%) say Sanders is too liberal and more caucusgoers (31%) say Sanders is almost to lose to Trump than they do for any other candidate.

When I blogged about our last Iowa poll in September, I noted that "I'd keep an eye on Buttigieg in Iowa." The reason I thought he could come up in the polls was his strong very favorable rating. It's a score that is highly correlated with vote choice.

Many candidates are liked in caucuses and primaries. After all, party faithful are choosing between candidates of their own party. The key, therefore, is to be loved, not just liked.

Buttigieg had the second best very favorable rating at 33% in our last poll. That was second best in the field. In other words, Buttigieg had a bunch of potential supporters that he simply hadn't converted. He has now brought them into his camp.

Additionally, he's picked up a few more folks. His very favorable score has climbed to 42%, which is the best of any of the Democratic candidates running for president. It's a sign, along with support among extremely and very enthusiastic voters that Buttigieg's backing is built on a solid foundation.

Warren is only a bit behind Buttigieg with a 36% very favorable rating. She's down from a 44% very favorable rating in our last poll. It's not inconceivable that Warren could pick up ground in our next poll, if you're looking at the very favorable ratings.

Of course, Warren's very favorable rating could fall again. The same warning holds for Buttigieg: Other candidates will go after him now that he stands at the top. A strong very favorable score now is far from a guarantee of one in the next poll.

One of the big hallmarks of Warren's campaign so far has been her enthusiastic supporters. You see it in the crowds that come to greet her at campaign events.

In our last Iowa poll, Warren led the horserace with 30% among those who said that they very or extremely enthusiastic about their first choice for the caucuses. That was 10 points ahead of her closest competitor, Biden at 10%.

Today, Warren's at only 18% among this same group. Given the sample size of this crosstab, this is within the margin of error of Biden (14%) and Sanders (18%). Warren's drop is the most precipitous of any of the candidates.

The candidate who has taken her place at the top is Buttigieg, who has rocketed up to 28% from 13% among extremely or very enthusiastic supporters.

This indicates that Buttigieg's voters aren't just with him because they don't like the other candidates. They are with him because they like him.

Interestingly, Warren doesn't seem to have lost any ground among those who aren't all that enthusiastic about their candidates. She's at 13% among those who are mildly or not that enthusiastic about their first choice. Back in September, she was at 14%.

Biden, on the other hand, has seen his support among the less enthusiastic voters go from 39% in September to 21% now. This suggests Biden lost a lot of voters who were not enthusiastic about him in the first place.

Our poll asked caucusgoers whether it was more important that the winner of the caucuses be someone who can beat Trump or that the winner shares their positions on major issues.

The clear majority, 63%, said the ability to beat Trump is more important, which is similar to previous polls on this question.

Buttigieg is ahead overall because he is dominating this group. Among those who prize electability, Buttigieg is lapping the field with 29%. The next closest are Biden at 17% and Warren at 16%.

Among those who say issue agreement is more important, Buttigieg is only at 15%. The candidate with the highest percentage among this smaller group is Sanders at 22%.

Much of Buttigieg's movement from September comes from those who say beating Trump is more important. Two months ago, Buttigieg scored 10% among those said beating Trump was more important, and 10% who said issue agreement was more important. That is, he's gained 19 points among the former group and just 5 points among the latter group over the last two months.

Interestingly, when specifically asked whether Buttigieg could beat Trump, just 16% of all caucusgoers said they were almost certain he could. Even among his own backers, only 27% said so. That's less than half the percentage of Biden's supporters who felt that way about Biden.

One wonders if there's a little leap in faith some new Buttigieg supporters are taking.

The topline number in our poll for Biden, 15%, is bad enough. Biden's lost ground in the horserace in every poll we've done so far. He now sits 10 points behind the leader, Buttigieg.

Go beneath the surface, and it doesn't get any better. In fact, you can argue that it gets worse.

Biden's very favorable rating (a metric highly correlated with horserace support) is also dropping. Biden's very favorable rating is down to 24% from 29% in September, 34% in June, 45% in March and 47% last December.

Among those voters who say they are certain of their caucus choice, Biden's earning 14%. In September, he was at 26% among this group.

Another way of looking at this is that Biden voters are about as likely to say they are certain to caucus for him now (26%) as they were in September (29%), even though he has fewer overall supporters. That means some people who said they were certain to caucus for him in September actually changed their minds.

Biden's at 20% among moderates and conservatives. That's down from 31% in September. He was at 31% in June too.

There is still time to turn it around: 58% say they at least actively considering Biden. That's little changed from 60% in September and 61% in June. Additionally, more likely caucusgoers (25%) say Biden is almost certain to beat Trump than they say of any other Democrat tested. That could be key in a cycle in which beating Trump is a priority.

Buttigieg's campaign made a decision in the past few months to move toward the center. He has, for example, been clear in his attacks on Warren and "Medicare for All." Caucusgoers seem to be picking up on this shift.

Take a look at where Buttigieg is scoring among different ideological groups. He's at 12% among those who say they are very liberal, 25% among those who identify as liberal and 30% among moderates and conservatives.

This pattern simply didn't exist in our September poll. Buttigieg was at 7% among very liberals, 14% among liberals who aren't very liberal and 8% among moderates and conservatives.

Back in June, Buttigieg's weakest group was moderates and conservatives. He earned 18% who are very liberal and liberals who aren't very liberal. He was at only 10% among moderates and conservatives.

In other words, Buttigieg's actually doing worse with very liberal caucusgoers than he was in June, even as he is doing considerably better among caucusgoers overall.

Today, 63% of likely caucusgoers believe Buttigieg's ideology is "about right". That's the highest of any candidate tested. A mere 7% believe he's too liberal, while 13% think he's too conservative.

Buttigieg seems to be taking advantage of a rising number of caucusgoers who think Warren is too far left. Now, 38% believe she is too liberal, which is up from 23% in March. That could be deadly for her campaign if voters think her leftward tilt hurts her electability.

But perhaps the candidate most harmed by this Buttigieg's tack to the center is Biden. Biden's down from 31% among moderate and conservatives in September and June to 20% now.