Now there are three respected polls (Monmouth, Des Moines Register, and Fox) that show Trump losing to a surging Ted Cruz in Iowa. Trump could certainly surge back in the next 50 days, but right now, Cruz is on track to win. He is relentlessly using social media data to build what he calls “very much the Obama model – a data-driven, grassroots-driven campaign.” And, he says, “it is a reason our campaign is steadily gathering strength.” Trump is relying on rallies and the endless free TV coverage the media provide him.

Trump promises he will bring a flood of new voters into Iowa’s caucuses, dwarfing the traditional total of 125,000 Iowans who vote in a typical presidential-election year — even though the caucus method requires voters to express their preference in public, over two hours, on what will probably be a frigid February evening.

David Brady and Douglas Rivers of the Hoover Institution say the demographics of Trump voters suggest they might not show up at the caucuses after all. Trump supporters are largely older, less wealthy, and less educated. Half of his voters have a high-school diploma, but just 19 percent have a college degree. Just over a third earn less than $50,000, while 11 percent make six figures or more. As pollster Kristen Soltis Anderson pointed out at NRO last week: “There is plenty of data to suggest that Trump voters are less likely to vote than others.”