Donald Trump is in the midst of an extremely rough patch for a campaign that overall has gone far from smoothly.

And now members of his own party appear to be turning against him, with nearly 20 percent of Republicans wanting Trump to drop out according to a recent poll.

The GOP presidential nominee has been stuck in a negative media cycle for seeming to suggest supporters use violence as a means of preventing rival Hillary Clinton from nominating judges, and criticizing the Muslim parents of a U.S. soldier killed in action.

His party, which had previously shown unease with his candidacy, has grown more rebellious in recent days. A string of Republicans has continued to come out against Trump, including the first sitting Republican member of Congress to openly endorse Clinton . One Republican has even launched an independent presidential campaign with support from a number of key Republicans in party's the anti-Trump movement.

It's enough to have pundits and the media openly questioning his mental stability, and asking if he may drop out before the election takes place.

Former Republican congressman and MSNBC television host Joe Scarborough called for the GOP to "dump Trump" in an op-ed published Tuesday in The Washington Post.

There is no evidence Trump is even considering packing it in. Trump campaign spokesperson Hope Hicks wrote in an email that, regarding the regarding the speculation, "There is no truth to this whatsoever."

It is not the first time this election cycle that questions have flown around about what may happen if a major party nominee is forced to drop out or withdraw from the ballot.

While Clinton was under investigation by the FBI with regards to whether she mishandled classified information, speculation swirled over what would happen to the Democratic ticket should charges be brought against her.

The chance is very slim that Trump will drop out, and he has not given any public indication that he is even remotely leaning toward that option. If he did make that decision for reasons unrelated to health or other grounds with a historical precedent, Princeton political historian Julian Zelizer said it would mark "new territory" that could lead to a lack of confidence in the Republican Party and the electoral process more broadly.

"The next election cycle, people would be very uncertain and uneasy about whether the nomination process is going to work," Zelizer said. "It's possible to imagine but we're not there yet."

Nevertheless, there is a procedure in place should Trump withdraw.

Rule 9 of the Republican National Committee rules governs "Filling Vacancies in Nominations," and stipulates that should the party's presidential or vice presidential candidate leave the ticket for whatever reason, the hole may be filled either by a reconvening of the national convention or by the party committee itself. The vice presidential nominee is not given any preferential consideration.

Should the committee elect to fill the vacancy — a seemingly more likely scenario given the logistics involved in organizing a second convention — Republican National Committee members representing a given state are entitled to cast the same number of votes as that state was entitled to at the convention. If the RNC members from any state are not in agreement about casting of their votes, the votes of that state are divided equally among members of the RNC voting.

The final stipulation of the rule is that no candidate may be chosen to fill a vacancy except by receiving a majority of the votes entitled to be cast in the RNC election.

The Republican National Committee did not immediately respond to a request for comment.

Should lightning strike and Trump drops out, potential candidates that could fill the vacancy would include House Speaker Paul Ryan, Republican primary runner-up Ted Cruz, and vice presidential nominee Mike Pence.

On the other side, the Democratic Party's charter and bylaws stipulate that the Democratic National Committee has responsibility for filling vacancies in the nomination for president and vice president. The rules say that "a special meeting to fill a vacancy on the National ticket shall be held on the call of the Chairperson, who shall set the date for such meeting" in accordance with procedural rules. The procedural rules say that — with some exceptions — all questions before the DNC are determined by a majority of eligible voters. Proxy voting is not permitted to fill a vacancy on the national ticket.

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