Since the release of the 2005 video showing Donald Trump making lewd comments about women, Colorado Senator Cory Gardner, Congressman Mike Coffman, and candidate for Senate Darryl Glenn have all called for Donald Trump to step aside.

"It is entirely new territory," Dr. Norman Provizer said.

Provizer is a political science professor at Metropolitan State University of Denver. He says just one month before the election, this is unprecedented. He says it is possible for Trump to pull out of the race at this point, but not likely.

"So, it's getting very difficult logistically to do anything," Provizer said. "A large number of states have already begun voting. Early voting has started. What do you do with all of that stuff? It's a mess."

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Colorado Secretary of State Wayne Williams says more than 20,000 people in the military already have their ballots and most counties have already printed ballots. Mail ballots start going out around the state on October 17.

The complications continue with the electoral college. Electors actually pick the President. In Colorado, electors are bound by law to vote for the designated candidate. Provizer says writing in Mike Pence for President probably won't work.

"You're allocated those electors. Who are the Pence electors? There really aren't any," Provizer said.

Plus, Provizer says states run elections by their own set of rules.

"That's one of the complications in this situation," Provizer said. "There's no one general rule where you can say okay we can go ahead and do this in every state. Every state's going to be different."

Provizer says Trump's allies across the Republican Party were already fragile. He wonders if this video will topple Trump's campaign.

"He's been managing to peel off support as opposed to add on support over time," Provizer said.