One notable left-leaning election forecaster questioned Vice President Kamala Harris' choice of Minnesota Democrat Gov. Tim Walz to be her running mate in this year's election.

Nate Silver, polling aggregator FiveThirtyEight founder who previously said he intends to vote for Harris in November, admitted "I'm not into Tim Walz" during the Oct. 9 episode of Risky Business, the podcast he hosts with Maria Konnikova.

Walz's Oct. 1 debate performance against Republican vice-presidential candidate Sen. J.D. Vance, R-Ohio, and his past misstatements have put campaign staff under constant damage control.

Silver said Walz was "tactically not very good at going after J.D. Vance," whom he described as "an objectively better debater."

The statistician added that Walz was "obviously extremely nervous for the first 15 minutes of the debate, which is the part that people often remember."

Silver said that while the debate ultimately wouldn't matter much, it was Walz's "one job," so he "should really nail that debate."

"You don't want to make Trump and Vance seem sane," Silver said on the podcast, adding that Walz was "doing this whole nice guy thing."

Although he described Walz as "fine," Silver said he would have preferred Pennsylvania Gov. Josh Shapiro with Harris on the Democrat national ticket, which is opposing former President Donald Trump and Vance.

"There was this feeling of euphoria after Harris replaced Biden. And I think people therefore overrated everything she did in that period after that," Silver said

No Democrat has won the White House without winning Pennsylvania since 1948, Newsweek reported.

The Keystone State's 19 Electoral College votes are more than any of the seven key battleground states expected to decide the presidential election's outcome.

One reason Harris likely chose Walz was to help sure up support from labor organizations. However, Politico reported Tuesday that the Democrat ticket is struggling to win over key rank-and-file union members.

"Democrats' waning influence with unions, especially industrial, male-heavy groups like the firefighters and Teamsters, has been a major point of concern for Democrats since Harris took over the ticket from Biden, who was widely hailed by union leaders as a staunch ally of organized labor," Politico reported.

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