(CNN) First things first: The theme song of the week is The Critic .

A new CNN/Des Moines Register/Mediacom poll shows that South Bend, Indiana, Mayor Pete Buttigieg leads the Democrats among likely Iowa caucusgoers with 25%. It's a three-way fight for second between Massachusetts Sen. Elizabeth Warren (16%), former Vice President Joe Biden (15%) and Vermont Sen. Bernie Sanders (15%).

Buttigieg is clearly one of the -- if not the only -- frontrunners in the Iowa Democratic contest right now. Yet, some (like myself) have wondered aloud about whether Buttigieg will be able to translate his Iowa success into more diverse states like Nevada and South Carolina. That's because Iowa is overwhelmingly white and Buttigieg has consistently polled poorly among nonwhites (specifically African Americans ) nationally.

There's no doubt that some portion of Buttigieg's lower numbers with nonwhite voters has to do with lower name recognition, which isn't a problem for him in Iowa. I am, however, skeptical that lack of name identification is the root cause of Buttigieg's issue with nonwhite voters. Why? Buttigieg is polling far worse among the relatively few nonwhite likely caucusgoers in Iowa.

Although our last Iowa poll has an insufficient sample size to judge how nonwhite Democratic caucusgoers feel about Buttigieg, we can combine our last two Iowa polls (September and November) to get a good understanding of where nonwhite caucusgoers stand compared to white Democratic caucusgoers.

In our combined sample, Buttigieg scores a 50% favorable rating and an unfavorable rating of 26% among nonwhite likely caucusgoers. That makes for a net favorability rating of +24 points. This is not a particularly strong number for a Democrat among Democratic caucusgoers.

To put this net favorability rating into some perspective, it looks a lot more like the overall net favorability ratings for lagging candidates such as California Sen. Kamala Harris and New Jersey Sen. Cory Booker than it does for a frontrunner.

White likely caucusgoers score Buttigieg much more highly. He earns a 73% favorable rating and an unfavorable rating of 13%. That makes for a net favorability rating of +60 points.

In other words, Buttigieg's net favorablity rating is twice as high among whites than nonwhites in Iowa.

When we dig deeper, we see the same holds true with the all important very favorable rating. I've noted over and over again that Buttigieg's very favorable tipped me off to his potential rise. His very favorable rating among nonwhite likely caucusgoers in our combined sample is 20%. Again, that looks a lot more like the overall very favorable numbers for single digit candidates such as Harris and Minnesota Sen. Amy Klobuchar than a frontrunner.

His very favorable is about double that among white likely caucusgoers (39%).

Not surprisingly, first choice preferences among white and nonwhite likely caucusgoers demonstrate a similar pattern.

Across the two samples, Buttigieg is the first choice preference of 18% white likely caucusgoers. His support among nonwhite likely caucusgoers is a third of that, 6%. This 6% is not appreciably different from what national polls have found his support to be among nonwhite voters.

Now, I will say that there is time for Buttigieg to improve his numbers with nonwhite voters. Further, he doesn't need to win a majority of nonwhite voters to win the nomination. Buttigieg merely needs to be competitive.

Right now, though, Buttigieg clearly has an issue with nonwhite voters that could keep him from winning the nomination.