When will the presidential field start to shrink?

Throughout this year, the race for the White House has been pretty consistent as former President Donald Trump has led by a wide margin in the polls for the GOP nomination.

Meanwhile, President Joe Biden has faced limited opposition from Democrats.

Over the course of the next several weeks, expect a lot of changes among Republicans.

Traditionally the Iowa caucuses and the New Hampshire primary are periods of time in which some campaigns take off while others sail into the sunset.

Many Americans may be taking a good chunk of the rest of the year off, but other than a quick Christmas break, the Republican presidential campaigns are not.

For weeks, the presidential hopefuls have been barnstorming Iowa and New Hampshire and they have just days now to convince voters that they should be president. The Iowa caucuses are on Jan. 15.

For former President Trump, who is ahead by a wide margin in the polls, it's all about reminding his voters about how the caucuses work. At Trump's recent Iowa rallies, his campaign shows a video teaching people how to participate.

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For the candidates chasing him, there is a belief that voters are just beginning to make up their minds.

One example: A conversation we had with Susan Hjelle in Iowa earlier this month.

We found Hjelle at a Vivek Ramaswamy event. She voted for Biden in 2020, but may show up at Republican caucuses in a few weeks.

"I still like Joe Biden but Vivek came across very well," she said. "I am checking out the candidates because the debates are so disruptive."

One thing is for sure, expect the upcoming weeks to be a bit volatile because historically, not all campaigns make it past Iowa or New Hampshire.

In 2020, Michael Bennet, Cory Booker, Julian Castro, Marianne Williamson, John Delaney, Deval Patrick, and Andrew Yang dropped out of the Democratic race shortly before the Iowa caucuses or shortly after the New Hampshire primary.

In 2016, the last time Iowa had competitive Republican caucuses, Rand Paul, Mike Huckabee, Carly Fiorina, Chris Christie, Jim Gilmore, and Rick Santorum withdrew shortly before or shortly after the Iowa caucuses.

If history repeats itself, there is a good chance that at least one of the candidates will drop out in the next month, potentially shaking up the race, and possibly, creating competition for Trump.