Watch these counties first tonight for a glimpse into 'Iowa Silver.'

In Iowa, on caucus day, indications suggest a clear victory for the former president.

The former president has been a consistent frontrunner in surveys.

If Trump wins first place, the contest will still make news due to the low number of candidates remaining. The second-place finisher may be the only one left to compete with Trump.

Given that Nikki Haley and Ron DeSantis are only separated by a few points in recent surveys, it could be a long night for either of them to take home the silver medal.

To get an early glimpse into the statewide outcome, examine the results from these counties. They will provide insight into the overall race's contours.

The rural counties where Trump is expected to win big

Rural voters in Iowa are Trump's most ardent supporters.

These groups, including low-income, non-college-educated, and evangelical voters, are more likely to reside in rural areas and are essential components of Trump's voter base.

Iowa has many rural areas with low population density, with 48 out of its 99 counties having under 15,000 residents. This is good news for Trump.

Collectively, they add up to a powerful voting bloc.

Trump aims to increase his lead as much as possible in all 48 counties and beyond.

In deeply rural counties, where Trump received some of his lowest vote shares in 2016, he has the most work to do.

• Winnebago County, in the north (18.6%)
• Hancock County, also in the north (18.8%)
• Montgomery County, in the southwest (20.7%)
• Grundy County, in central Iowa (20.9%)
• Delaware County, near the eastern border (22.2%)

He had similarly low vote shares in the most evangelical rural counties.

Trump is expected to perform better in these counties than he did previously. The greater the margin, the more challenging it will be for both leading contenders, particularly DeSantis, to surpass him.

Counties with the most populated cities

Haley is running a campaign that differs from Trump's. Her approach, particularly on foreign policy and spending, is more attractive to non-Trump and pro-establishment GOP voters.

As a result, Haley over-performs with urban and suburban voters.

To succeed on caucus night, she must gather the most raw votes in the densest cities.

An ideal night for Haley would be like Marco Rubio's 2016 performance, where he received 23% of the overall statewide vote, mainly due to his impressive showings in urban areas.

Here are those counties, along with Rubio’s share.

• Polk County, home to Des Moines (26.9%)
• Scott County, home to Davenport (26.2%)
• The University of Iowa and Iowa City are located in Johnson County, which makes up 30.5% of the area.

Although Haley came in second in both the Des Moines Register/NBC News and Suffolk surveys this week, a majority of her voters express only mild or less enthusiasm about her.

Examine Haley's expected vote share and overall turnout in areas where she is predicted to perform well.

The ‘evangelical square’ in northwest Iowa

DeSantis has been attempting to convince voters of his social conservatism by discussing his stance on abortion and transgender surgery.

He aims to win the support of White evangelical voters, who have traditionally been influential in caucus outcomes, such as Ted Cruz and Rick Santorum.

Despite the effort, only 51% of evangelicals chose Trump as their first pick in the DMR survey.

In the state, DeSantis received 22% of the evangelical vote, which is six points higher than his overall performance.

Observe the performance of DeSantis among that group on caucus night by examining the four counties in the northwestern corner of the state, which have a high percentage of White Christian populations.

• Lyon County (87%)
• Osceola County (83%)
• O’Brien County (82%)
• Sioux County (81%)

In Shelby County, Pocahontas, and Monroe, the return rate for watches is 83%, 83%, and 82%, respectively.

For a strong second place finish, DeSantis must not only outperform in these counties but also do well with evangelicals statewide, as these counties have small populations.

Tomorrow's outperformance for DeSantis will depend on strong evangelical margins in the northwest.

Calhoun County could provide hints at the statewide result

Calhoun County, a rural county in the western part of the state with a population of 9,725 people, closely mirrored the state's voting preferences in 2016.

In Calhoun, Cruz received 28.6% of the vote, while statewide he obtained 27.6%.

In Calhoun, Trump obtained 24.4% of the vote, which is only 0.1 percentage points less than his statewide total of 24.3%.

In Calhoun, Rubio's share was approximately 21.7%, while his overall percentage was about 23.1%.

No other county got this close to the overall result.

The statewide result can be determined by examining Calhoun's results, as it has a small population and the results will come in quickly.

The usefulness of all these counties to the overall vote and whether Calhoun remains a leading indicator will become clear when the results are announced tonight.

Fox reporters are following the campaigns as they make their last-minute pitches to voters, with continuous coverage throughout caucus day.

The caucuses will commence at 8 p.m. ET (7 p.m. in Iowa). These events typically involve speeches from the campaigns and other formalities, so anticipate a delay before the first results are announced.

The Planet Chronicle Voter Analysis and Decision Desk will provide exclusive insights and call the race throughout the evening.

Bret Baier and Martha MacCallum will provide special coverage at 10 p.m. ET.