The matchup could have an impact on critical undecided voters.
The vice-presidential debate between Tim Walz and JD Vance could prove to be a major factor in the presidential election -- given how close the race is and its potential impact with undecided voters.
The 90-minute CBS News showdown starts at 9 p.m. ET in New York City. ABC News Digital will live blog throughout the day and evening, pre-debate coverage will air at 8 p.m. on the ABC network and stream on ABC News Live -- followed by the debate itself and post-debate analysis.
White House press secretary Karine Jean-Pierre wouldn't say during the White House press briefing on Tuesday whether President Joe Biden would watch the vice presidential debate, but she said the president has "complete confidence" in Walz.
"He continues to be very busy with all of the events happening today," she said during Tuesday's briefing. "But he has complete confidence in Tim Walz."
Former Rep. Tulsi Gabbard spoke to ABC News Live on Tuesday where she criticized Walz's lack of media interviews, predicting that it will show in the debate.
"I think there's going to be a stark contrast here, given JD Vance has been out on the road doing multiple interviews," she told ABC News Live. "I think he's done more interviews than any candidate in this election, whereas Tim Walz has been very quiet on that front."
"I think this opportunity tonight, I hope, will not be more of the same kind of political theater that we've seen in so many of these debates, but actual substantive discussion and debate and accountability," Gabbard -- who endorsed Trump -- continued.
-ABC News' Casey McShea
Ahead of Tuesday's debate, Adrienne Elrod, Harris campaign senior adviser and spokesperson, made an appearance on ABC News Live and said that Walz is taking it "very, very seriously."
"Gov. Walz is taking this debate very, very seriously because you understand the magnitude of this moment," Elrod said. "He's going to continue to really talk about the Harris-Walz priorities, what their administration would look like, lowering costs for middle class families, protecting the Affordable Care Act, not getting rid of it."
-ABC News' Casey McShea
CBS News, the network hosting the debate, said that the candidates' microphones will not be muted, but clarified in a press release that it "reserves the right to turn off candidate microphones."
This is a shift from the CNN presidential debate in June and the ABC News presidential debate held earlier this month, where microphones were muted unless it was the candidate's turn to speak.
Read more here.
-ABC News’ Oren Oppenheim
