DES MOINES, Iowa Former Vice President Joe Biden has played a role in some of the most controversial domestic and foreign policy decisions from the 1970s to the 2010s.

He co-authored the 1994 crime bill, lobbied for the 2005 bankruptcy reform bill, and voted for both the North American Free Trade Agreement and the Iraq War. Despite that record, Biden began the presidential race as a front-runner and continues to top the polls in early states, including several recent surveys in Iowa , the first-in-the-nation caucus state where he had previously been weaker.

Overall, Tuesday nights smaller debate rumble Biden was joined by billionaire businessman Tom Steyer , former South Bend, Indiana, Mayor Pete Buttigieg , and Sens. Bernie Sanders (I-Vt.), Elizabeth Warren (D-Mass.) and Amy Klobuchar (D-Minn.) was a genteel affair.

Foreign policy and international trade, previously lightly discussed, took up large chunks of time. And while there were disagreements between the candidates Tuesday night, in the final stretch before the Iowa caucuses, they largely avoided aggressively attacking one another. Warren and Sanders passed on re-litigating what happened in their 2018 meeting , and Biden avoided a pile-on about the Iraq War and his support for international trade deals protested bitterly by labor unions.

The decision to avoid head-on fights was motivated no doubt by the fact that much of the Democratic electorate seems to have little appetite for such squabbles, preferring the focus be kept on attacking Trump and not doing too much lasting damage for the general election.

The greatest beneficiary of the debates calm tone was Biden. Tuesday nights debate was the last chance Iowans had to hear Biden answer in greater detail about his record before they head to caucus sites on Feb. 3.