Donald Trump went to Lowell, Mass. — a town about five miles south of the New Hampshire border — for one of his now-trademark big-arena rallies on Monday night. This is what the crowd looked like per WaPo's Jenna Johnson.

The building — named after the late Massachusetts Sen. Paul Tsongas (D) — holds 8,000 people, and local officials were estimating that it was filled to capacity or beyond. That is a MASSIVE amount of people — especially considering that the high temperature in Lowell yesterday was 29 degrees and Trump's rally didn't start until the evening.

This is what the line to get in looked like.

I know that crowd size is an uncertain indicator in politics. After all, if crowd size at rallies was determinative, Bernie Sanders, not Hillary Clinton, would be the heavy favorite to be the Democratic presidential nominee.  That skepticism of crowd size goes double for Trump since there are plenty of people who go to see him simply for the spectacle or to be near a celebrity, not because they have any designs on voting for him.

And yet, the willingness of so many people to wait so long in such cold temperatures simply for the chance to see Trump speak would suggest that the idea that his supporters won't be the sort of people to sit through the long caucus process of Iowa or turn out to vote in the frigid cold of New Hampshire might be misguided.

Republican presidential candidate Donald Trump told supporters that the recent diplomatic fallout between Iran and Saudi Arabia is over oil at a Mass. rally on Jan. 4. He said that after the Iran nuclear deal, Iran 'got' Iraq, and was now after Saudi Arabia. (Reuters)

Ditto the idea that Trump's bubble would burst or the ardor with which his backers regard him would fade. The Iowa caucuses are in 27 days. New Hampshire votes in 35 days.  The time is now, and people are still showing up in droves to see — and cheer — Trump.

Crowds like the one in Lowell on Monday should make clear to the last few lingering doubters that the Trump phenomenon isn't going away as voters begin the process of picking a Republican presidential nominee. Hell, he might even be getting stronger.

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