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Joe Biden has a big lead among African-American Democrats — and African-Americans make up about 25 percent of the party’s voters. Among Latinos, who make up almost 10 percent, Biden is neck-and-neck with Bernie Sanders for the lead.

Biden’s strength with minority voters is an enormous advantage in the highly diverse Democratic Party. And yet this morning some pundits are wondering whether Biden is finished — because he appears to have come a disappointing fourth in Iowa.

That’s nuts.

Readers of this newsletter know that I think Biden has weaknesses as a presidential candidate. But he also has major strengths, including his experience, his political skills, his middle-class image and his evident humanity. Democratic voters (and political journalists) would be making a mistake to disqualify him based on a disappointing finish in one fairly small, overwhelmingly white, highly unrepresentative state.