There are 15 days from now until voting ends, and in addition to monitoring the polls and the fortunes of your preferred candidates, I suggest you keep an eye on the progress in the coming days of the caravan of Central American refugees who started crossing into Mexico over the weekend.

It sure looks like the Trump administration wants to turn this story into its closing argument, riling up the base by stoking fear of a brown wave descending on Brownsville, Texas, and accusing Democrats (and of course George Soros) of making it all happen.

Polls still indicate that Democrats and young people are fired up to vote. There was a burst of Republican enthusiasm around the Kavanaugh fight, but there are signs, perhaps, that has ebbed a bit. An NBC/Wall Street Journal poll released Sunday gave the Democrats a 9-point generic ballot advantage over the Republicans.

That’s the same as the 9-point Real Clear Politics average advantage for Republicans in late October 2010. The Republicans picked up 63 seats that year. A 63-seat gain seems impossible for Democrats because of gerrymandering, but that 9-point cushion is nevertheless formidable and has the GOP plenty worried.

“ Bush and Rove would say just about anything to win that election. But Trump will do anything. And that is what’s scary here. ”

So the Republicans have been playing their usual fear cards. But they’re coming up snake eyes. Fear of Nancy Pelosi isn’t working all that well and indeed now may backfire after that ugly demonstration against her when she appeared in Miami to campaign over the weekend. Members of the openly racist Proud Boys group were among those yelling “communist!” at the House Democratic leader. They may actually succeed in turning Pelosi into a figure of sympathy and solidarity.

The fear of Democrats taking away your health care has bombed, since Mitch McConnell admitted late last week that if they solidify their majorities, Republicans will take another whack at Obamacare. McConnell also stepped on the tried-and-true fear storyline of the Democrats slashing Medicare and Social Security, since he also said last week that the Republicans are taking aim at those programs, too.

It’s amazing, in fact, how horribly McConnell has cocked things up for his party. If a few red-state Democratic senators (besides Joe Manchin, who seems to be in the clear) eke out wins, it will be because McConnell committed the oh-so-un-McConnell-like mistake of telling the truth for once about Republican plans.

That leaves the old reliable Republican fear cards, the ones that long predate Trump: national security and race, in this case fused into a narrative Trump and other Republicans are trying to build about the Honduran refugees attempting to enter Mexico. That’s where their closing argument is headed, and it’s terrifying to imagine where it might climax.

The Republicans’ only hope of salvaging these elections—well, aside from cheating, which they’re also doing, most transparently in Georgia, but everywhere they can get away with it—is for their base to be absolutely panic-stricken with fear.

So Trump warns, as he did in Arizona over the weekend as reported by my colleague Scott Bixby, that the Honduran migrant caravan includes “bad people” and “tough people” and would “overwhelm our nation”; and that the Democrats, whom Trump now regularly calls “evil people,” want all these bad hombres to come to America to rape and steal and pillage and of course vote. He doesn’t necessarily say all this explicitly, but it’s obviously what he wants people to think.

This isn’t so different on one level from standard Republican electoral fear-mongering. I might like to know, for example, what all the admirable “non-practicing Republicans” (in Nicolle Wallace’s cheeky phrase) who are saying all the right things about Trump today think in retrospect about that hideous 2002 Saxby Chambliss ad in Georgia. It used shots of Saddam Hussein and Osama bin Laden to scare voters into thinking that his Democratic opponent Max Cleland was soft on the bad guys—as a sign of his softness in real life, he’d left three of his limbs in Vietnam while fighting for his country there, as Chambliss embraced five student deferments. But be that as it may, there’s a difference between George W. Bush and Donald Trump; even, yes, between Karl Rove and Donald Trump.

Bush and Rove would say just about anything to win that election. But Trump will do anything. And that is what’s scary here.

You’ve seen his tweets about militarizing the border. You just know that he (and aide Stephen Miller) would love nothing more than to send troops to the border before Nov. 6. It is exactly what authoritarians like them throughout history do—they make blustery shows of force against largely nonexistent threats. This is what Trump thinks leadership is.

Bush and Rove wouldn’t have gone this far. Mind you, they went pretty far, forcing Iraq war votes in Congress during the heat of election season in 2002. But still, that did not involve actual substantive movement of troops away from their normal stations, at a cost of billions of dollars, to try to produce a desired political outcome.

And Trump hasn’t done it either of course—yet. But if he thinks it’ll help Republicans win, if he thinks it’ll get his worshippers to the polls, he’ll do it in a heartbeat. The impulses that constrained Bush and Rove, that made even Rove understand that he couldn’t just do anything he wanted, are meaningless to Trump.

I mention the 2002 midterm because it was the ghastliest in modern history. There’ve been nasty midterms on both sides, but 2002 is the only time one party (the GOP) created an us-versus-them, with-us-or-against-us mood to get people to vote based on their paralyzed fear of The Other. With Trump, we have reason to fear that these next two weeks are going to make 2002 look like a student council election. Keep one eye fixed on the Rio Grande.