These Iowa counties could give the clearest picture yet of the strength of Trump's support

The true state of the modern-day GOP could reveal itself after tonight's Iowa caucuses — especially if voters come out in large numbers in specific counties.

Despite losing the state's Republican primary contest in 2016 — and arguing Texas Sen. Ted Cruz stole it — Donald Trump thrived in certain parts of the region. And comparing today's result with that of eight years ago could give a clear picture of how the Republican Party has changed, according to Politico.

For Trump, the rural swaths of Iowa went MAGA in the past, but when it came to more populated metropolises he struggled.

Politico said it may be critical to keep an eye on the potential bellwether counties, specifically Fremont.

"Trump's strongest 2016 county was small, rural Fremont, in the state's southwest corner, sandwiched between Missouri to the south and Nebraska across the Missouri River to the west," Politico's Steven Shepard wrote.

"He won 42.7% of the vote there — the only county in which he broke the 40% mark (as a baseline, Trump received 24.3% of the caucus vote statewide.)"

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Other counties that could show Trump's renewed reign over the party run along the southern border with Missouri. Politico notes his "five strongest were all south of I-80, which runs from the Quad Cities through Des Moines and into Omaha, Nebraska."

In contrast, Trump struggled in Sioux County where he won only 10.9% of the vote, which the outlet notes is "one of the state's most Republican counties." The result there could predict if other traditionally non-MAGA areas will sway towards the Republican frontrunner.

Places where Trump isn't as historically dominant include Story County with 15.3% support in 2016, Lyon County with 15.6%, Winnebago County with 18.6% and Marion County with 18.8%.