Minnesota Gov. Tim Walz and Ohio Sen. JD Vance are hours away from the first and only vice presidential debate.

As the latest Fox News Power Rankings reveal, Vance starts the evening with a lead on the economy and immigration, while Walz has an advantage on abortion.

Vice presidential hopefuls do not attract as much attention as their bosses when they debate, but as Fox News’ Arnon Mishkin argued Monday, they have changed the direction of at least six elections in the last 50 years.

In most cases, these debates are won on policy. Voters are not as familiar with these nominees as they are with former President Donald Trump or even Vice President Kamala Harris, and they do not need to make their choice.

The smart play for these vice presidential candidates is to focus on the major issues at stake and how their administrations would solve them.

FOX NEWS POWER RANKINGS: HARRIS TICKS UP AND SENATE REPUBLICANS TAKE CHARGE

That is especially true for Walz on the economy and immigration, since the Harris campaign continues to lag on those issues. Vance, meanwhile, has struggled with poor favorability ratings, so his challenge is to hammer the popular parts of the Trump agenda and avoid wading into the culture war trenches.

There are also style points up for grabs. Many voters will only ever see this debate in short clips on social media, so acting like a policy wonk is less likely than ever to get the job done.

Trump continues to hold an advantage on two of the top three issues in this campaign. He leads on the economy by nine points and immigration by 11.

Those numbers have barely budged since Harris and Trump debated. In August, when the Power Rankings last looked at the major issues, the former president led on the economy by eight and immigration by 13.

Harris is far out in front on abortion. She leads by 17 points on that issue, also a negligible movement since the last tracker (Harris +18).

This tracker includes polls from Fox News, Quinnipiac, CNN/SSRS, NBC News and the New York Times/Siena.

Trump lost a point in the horse race after his debate with Harris while the vice president gained one; these modest shifts mirrored those after the first debate in 2020.

Together, these results suggest that the cause of Trump's slight decline was style rather than substance.

Conversely, while Harris won the debate and held on to her advantage on abortion, she has not consistently closed the issues gap, particularly on immigration.

That is not ideal for her, given the economy (38%) and immigration (17%) are two of the top three issues for voters. A recent Fox News national survey showed those issues and abortion (16%) were the only three that a double-digit percentage of voters called their "most important" issue in deciding their vote.

According to the same survey, Harris has strong leads in issues outside the top three. That includes health care, helping the middle class and climate change. These are "bread and butter" issues that the left has relied on to drag out base voters in previous elections.

The Democratic candidate also has a lead in uniting the country and, as consistent with previous trackers, having the right temperament for the job.

The candidates are evenly divided on national security. Neither has an advantage in handling a crisis that puts the country at risk, being commander in chief or decisions about using nuclear weapons. Trump’s temperament deficit should give Harris an opportunity to lead on some of these qualities, but that has not materialized.

ARNON MISHKIN: JD VANCE IS AN EXCELLENT DEBATER AND PRACTICES FOR THE DEBATE EVERY SUNDAY

Finally, voters prefer Trump on foreign policy. He has a six-point lead in handling the Israel/Hamas war and an eight-point lead on the Ukraine/Russia war. 

Tuesday is debate night. Walz and Vance will face off at an event hosted by CBS News in New York City. Fox News will simulcast the debate with special coverage anchored by Bret Baier and Martha MacCallum at 8:20 p.m. ET.

Fox News Media has proposed a second Harris-Trump debate to be moderated by MacCallum and Baier in October.

Voters can now cast a ballot in more than half of all states, including Pennsylvania, Michigan, Wisconsin and North Carolina.

While many voters are expected to cast a ballot early, Election Day itself is just five weeks away.