Is the Republican presidential primary over already?

Not quite, but it’s a reasonable question after New Hampshire’s first-in-the-nation primary delivered a clear victory for Donald Trump last night. And if your definition of “over” is whether Trump is now on track to win without a serious contest, the answer is probably “yes.”

With nearly all the counting done, he won 55 percent of the vote. His only remaining rival, Nikki Haley, won 43 percent.

Trump’s 12-point margin of victory is not extraordinarily impressive in its own right. In fact, he won by a smaller margin than many pre-election polls suggested.

What makes Trump’s victory so important — and what raises the question about whether the race is over — is that New Hampshire was Haley’s best opportunity to change the trajectory of the race. It was arguably her best opportunity to win a state, period.

If she couldn’t win here, she might not be able to win anywhere — not even in her home state of South Carolina, where the race turns next. And even if she did win her home state, she would still face a daunting path forward.

Trump leads the national polls by more than 50 percentage points with just six weeks to go until Super Tuesday, when nearly half of all the delegates to the Republican convention will be awarded. Without an enormous shift, he would secure the nomination in mid-March.