(NewsNation) — Vice presidential candidates Ohio Sen. JD Vance and Minnesota Gov. Tim Walz will go head-to-head in one week.

Without a second presidential debate on the books, the Oct. 1 vice presidential debate could be the last chance either campaign has to sway crucial undecided voters. CBS News will moderate the debate in New York City.

The last time a vice presidential debate drew more viewers than a presidential debate was in 2008 when then-Sen. Joe Biden faced off with then-Alaska Gov. Sarah Palin.

How are JD Vance, Tim Walz preparing for the vice presidential debate?

Both Vance and Walz are deep in debate preparation when they’re off the campaign trail.

Rep. Tom Emmer, R-Minn., will stand in for Walz as part of Vance’s debate prep, while Transportation Secretary Pete Buttigieg will play Vance’s role during Walz’s preparations.

Independent and more moderate voters may decide the November election, meaning both candidates may try to paint their opponent as extreme.

What are JD Vance’s, Tim Walz’s strategies going into the debate?

The latest polling from Decision Desk HQ and The Hill suggests a close race, with Harris having a 3.6-point lead over Trump as of Tuesday.

Harris has about a 2-point lead in key battleground states. Amid a neck and neck race, anything the vice presidential candidates say at the debate stands to make an impact.

Vance will likely try to tie Harris closely to the Biden administration and convince voters they’re no better off since Biden and Harris entered the White House. He’s also likely to talk about the number of migrants entering the U.S. under the current administration.

As for Walz, the governor will likely mention Vance’s comments about “childless cat ladies” and paint him as a threat to reproductive rights.

Why the debate between JD Vance and Tim Walz matters

This will be the last time candidates from either party will face off on a debate stage unless Trump agrees to an Oct. 23 CNN debate.

The Democratic National Committee launched new billboards showing Trump dressed as a chicken and accusing him of being too scared to debate Harris, who accepted the debate invitation this week.

“I’ve done two,” Trump said. “Had Biden and, after that, he had to drop out. He shouldn’t have dropped out, to be honest. He got 14 million votes. She got none.”

On Saturday, Trump said it was too late for another debate since early voting has already started in some states.

However, Trump previously debated in October both against Biden in 2020 and Hillary Clinton in 2016.