Over the past three weeks, Hillary Clinton’s chances to win the presidency have fallen. Her lead over Donald J. Trump has shrunk to between one and four percentage points nationwide, depending on which polls you count, and which candidates are included.

Here’s one way to think about the race: Three weeks ago, a Clinton loss was about as likely as a missed 35-yard field-goal attempt in the N.F.L. Today, circumstances have moved that kick 10 yards farther from the goal line.

(And here’s something for those of you yelling, “Not another sports analogy!” Mr. Trump’s chances of winning are roughly equal to the chance of drawing two consecutive cards of the same suit.)

Another way to think about it: In terms of the candidates’ chances, we’re in about the same place we were before the conventions. Clinton supporters should be about as concerned as they were two months ago, before the parties gathered. Trump supporters should be roughly as hopeful as they were then.