We are blessed with two fine candidates, but it’s entirely possible that when primary season ends on June 3, we will still lack a clear nominee. Barack Obama and Hillary Clinton could each still believe that the nomination could be his or hers at the national convention in Denver in August.

In that situation, we would then face a long summer of brutal and unnecessary warfare. We would face a summer of growing polarization. And we would face a summer of lost opportunities — lost opportunities to heal the wounds of the primaries, to fill the party’s coffers, to offer unified Democratic ideas for America’s challenges.

If we do nothing, we’ll of course still have a nominee by Labor Day. But if he or she is the nominee of a party that is emotionally exhausted and divided with only two months to go before Election Day, it could be a Pyrrhic victory.

Here’s what our party should do: schedule a superdelegate primary. In early June, after the final primaries, the Democratic National Committee should call together our superdelegates in a public caucus.

Of the 795 superdelegates, over 40 percent have not announced which candidate they are supporting; I’m one of them. While it would be comfortable for me to delay making a decision until the convention, the reality is that I’ll have all the information I reasonably need in June, and so will my colleagues across the country.