Then there was an exchange on the Democratic Party's appeal to black voters, which included Biden's rather extraordinary assertion that "it comes out of the black community" in terms of support.

This statement sparked an incredulous response from Harris and Senator Cory Booker, the two black candidates on stage.

Harris said that minority voters were the "backbone" of the Democratic Party that was too often taken for granted.

The real fireworks did not hit until the end of the debate, however, when Senator Amy Klobuchar and Gabbard took turns questioning what they considered to be the relatively subtle political summary of Buttigieg.





Buttigieg entered the debate with a target on his back. Recent polls in Iowa and New Hampshire, the first two states in the Democratic Party's presidential nomination process, have shown that the mayor of Indiana's fourth largest city has risen to a statistically significant advantage.





Noting that he has a history of success in winning elections in a swinging state and in passing legislation to Congress, Klobuchar said "I think the experience should be important".





Gabbard followed Buttigieg's suggestion to send US troops to Mexico to help fight drug cartels.





Buttigieg, who clearly anticipated the attacks, had his answers ready.





"The Washington experience should not be the only experience that matters," he told Klobuchar. "There are over 100 years of experience in Washington on this stage right now, and where are we now?"





As for Gabbard's criticisms, he said he had more than enough experience to know that he should not sit with a "murderous dictator" like the Syrian Bashar al-Assad, which Gabbard did in January 2017.





In just over two months, the Democrats will begin the process of selecting their party's presidential candidate for 2020. In their concluding remarks after the sometimes harsh debate, the Democrats declared themselves "the candidate to tiptoe with Donald Trump ", in the words of Harris.





The debate took place on the same day that a Marquette University poll showed that Donald Trump beat all the major Democratic candidates head-to-head in a hypothetical general electoral meeting in Wisconsin, considered one of the major swing states of 2020.