It’s Hard To Win A Senate Race When You’ve Never Won An Election Before

Politics doesn’t have a farm system in the way that professional baseball does. But it has a hierarchy of its own for cultivating political prospects. The path usually goes something like this: First, a candidate wins some relatively minor, local office like city council or state representative. Then, they either win a seat in the U.S. House or a statewide office like attorney general. Only then do they run for U.S. Senate or governor.

Most of the Democrats running in competitive Senate and gubernatorial races have followed a version of...