Related video: Trump says no to another debate with Harris

(NEXSTAR) – Republican J.D. Vance and Democrat Tim Walz will meet Tuesday in the lone vice presidential debate of the 2024 election, bringing together undercards who have spent two months going after each other and the opposing nominees who top the major-party tickets.

The matchup, hosted by CBS News in New York, might not carry the same stakes as the Sept. 10 debate between former President Donald Trump and Vice President Kamala Harris. But it offers their top lieutenants a fresh opportunity to introduce themselves, vouch for their bosses and fulfill a time-honored role of a running mate: attack dog. It will involve the biggest television and online audience either No. 2 will see before Election Day.

The CBS News Vice Presidential Debate will stream live in the player below once it begins at 9 p.m. EDT.

Trump declared on Truth Social Monday that he will do posting a “personal play by play” of the debate as it happens. The debate is scheduled to start at 9 p.m. ET and last for 90 minutes.

Harris, who gave an update on the destruction of Hurricane Helene from the headquarters of FEMA Monday, hadn’t directly addressed the debate on social media as of Monday afternoon.

What to expect

Host CBS has announced that moderators will not be fact-checking candidates’ claims during the debate, instead they will leave it up to Vance and Walz to correct each other.

Vance, a 40-year-old senator from Ohio, is expected to spar with Walz, the 60-year-old governor of Minnesota over the economy as they both try to establish an advantage. Vance and Trump have attacked Harris over inflation and asserted an advantage when it comes to boosting U.S. manufacturing, while Harris and Walz have tried to present themselves as champions of the middle class.

Abortion is another topic that will likely come up, with Democrats hoping to sway voters concerned about abortion rights and reproductive health care. Walz has spoken in the past about how fertility treatments enabled he and his wife Gwen to have their daughter. The Democratic party has hammered Vance about his past comments accusing “childless cat ladies” of influencing the country’s future.

Vance and Trump, on the other hand, have struggled for a consistent message on abortion rights — a reflection of how politically fraught the issue is for Republicans since support for abortion access has increased since the 2022 Supreme Court decision to overturn Roe v. Wade and end a woman’s constitutional right to terminate a pregnancy. Trump brags about appointing conservatives who helped strike down Roe and return abortion regulation to state governments. Many Republicans now want to go beyond state bans and place federal restrictions on the procedure, but Trump has indicated that overturning Roe is enough. He has also waffled on how he’ll vote on a Florida referendum that would expand abortion rights.

Vance said in August that Trump would veto a national ban if it cleared Congress. A couple of weeks later, during Trump’s debate with Harris, the former president demurred on an answer, saying, “I didn’t discuss it with J.D.” The Harris campaign has amplified audio of Vance saying as a Senate candidate that he would like to see abortion outlawed nationwide.

This combination of photos shows Democratic vice presidential candidate Minnesota Gov. Tim Walz, left, at the DNC on Aug. 21, 2024, in Chicago, and Republican vice presidential nominee Sen. JD Vance, R-Ohio, on Sept. 25, 2024, in Traverse City, Mich. (AP Photo)

What the polls say

With a little more than a month left before the presidential election on Nov. 5, both Vance and Walz are under pressure to give their running mates the best possible chance to win.

Recent polls show Harris with a slim lead of about four points over Trump, according to the average from The Hill/Decision Desk HQ. In a number of battleground states, however, the race is far closer and considering the margin of error Trump could have a stronger position than the top line results indicate.

The Associated Press contributed to this report.