If we run last night’s events through the “Five W’s” of straight-up journalism, we don’t hit the reef until the end of the formula. Who? Joe Biden. What? Defeated Bernie Sanders in three key primaries. Where? In Florida, Illinois and Arizona. When? Last night.
Why? That’s the reef.
The numbers by themselves are stark. In Florida, Biden defeated Sanders by nearly 40 percentage points. In Illinois, the margin was nearly 25 points, and in Arizona, the margin was 12 points. Those wide margins ensure that Biden’s final delegate haul from last night will be substantial; to secure the nomination, Sanders will now need to win 61 percent of the remaining delegates.