Democratic senator reportedly trying to organize a Biden drop-out push among his colleagues

• Sen. Mark Warner is reportedly trying to organize his colleagues to push for Biden to drop out.
• Biden has continued to face questions about his political viability in the wake of his bad debate.
• One senator said there's a "sense among many that the current path may not be sustainable."

As President Joe Biden continues to face questions about his political viability in the wake of his poor debate performance last week, one Democratic senator is reportedly nearing a tipping point.

According to the Washington Post, Sen. Mark Warner of Virginia is trying to gather a group of his Democratic colleague to ask Biden to withdraw from the race.

"Like many other people in Washington and across the country, Senator Warner believes these are critical days for the president's campaign, and he has made that clear to the White House," Warner's spokesperson, Rachel Cohen, told the Post.

Another Democratic senator told the outlet that "there is a sense among many that the current path may not be sustainable for him" and that Biden "obviously has to show strength right now."

As of Friday, no Democratic senator has called for Biden to step aside, though many have remained silent or dodged questions about whether they have confidence in him going forward.

Two House Democrats — Reps. Lloyd Doggett of Texas and Raúl Grijalva of Arizona —have publicly called for Biden to drop out, while two others have declared that former President Donald Trump will win the election.

Meanwhile, Biden publicly affirmed on Friday that he's "staying in the race" during a campaign speech in Wisconsin.

Biden is now in a critical moment for his campaign, with some pining for Vice President Kamala Harris — or another potential Democratic candidate — to take his place at the top of the ticket.

A key moment for the president will be his sit-down interview with ABC's George Stephanopoulos, which is set to air at 8pm ET on Friday.