The pleas to step aside came from many corners of the GOP universe, including Hugh Hewitt, the conservative radio host, and South Dakota Sen. John Thune, a member of the Republican congressional leadership.
Trump has so far defiantly rejected calls to withdraw. But even if Republicans managed to persuade him to bow out, their political headache would not suddenly vanish. An attempt to replace Trump on the ticket would pose staggering logistical hurdles.
For one thing, Trump’s name will undoubtedly remain on the ballot.
Across the country, election officials have already prepped and printed voting materials. Overseas and military voters must receive their ballots 45 days prior to the election, a deadline that passed last month.
And in states that offer early voting — including swing states such as Florida and Iowa — more than 400,000 people have already cast ballots, according to a database maintained by University of Florida professor Michael McDonald.
“The election is already underway,” McDonald said in an interview. “There is no way to replace Trump's name on the ballot.”
The mechanics of designating an alternative GOP nominee to Trump are also thorny.
Under Republican National Committee rules, the party has no authority to unilaterally dump the nominee. An attempt to change the rules would be “really unprecedented and probably create a civil war and lawsuits,” said one GOP elections expert who was granted anonymity to speak frankly.
The party does have the authority under Rule 9 of the RNC rules to name a replacement if a candidate dies or otherwise vacates the nomination. That means Trump would have to willingly step aside for Republicans to tap a new nominee.
In that unlikely event — Trump told the Wall Street Journal on Saturday that there is “zero chance” he’ll withdraw — the RNC rules committee would then vote on a new nominee. Most of the Republicans calling for Trump to step aside have floated vice presidential nominee Mike Pence as a replacement.
But that could set the stage for yet another battle for a party still scarred by its fractious primary, when Texas Sen. Ted Cruz ran a detailed but ultimately unsuccessful operation exploiting complex party rules to scoop up stray delegates who might have otherwise gone to Trump.
Even if the party were to settle on a replacement, it would then take on the tall task of persuading voters to line up behind its new pick, even though that person’s name would not be on the ballot.
“The voters would be confused. They would still see Trump's name on the ballot. They would still have to effectively cast a vote for Trump,” McDonald said. “How many people would know that vote was not actually for Trump but for another person?”
Republicans could also look to an even more convoluted path to stop Trump: the electoral college.
When people vote in presidential elections, they are technically choosing their state’s electors, who will vote when the electoral college meets in December.
Under one scenario explained by UC Irvine law professor Rick Hasen, the Republican Party could urge electors won by Trump to give their electoral votes to an alternate candidate such as Pence.
Hasen called such a move “an electoral college Hail Mary.”
“It requires a number of things to happen,” Hasen said in an interview. “It requires [Hillary] Clinton to not get a majority [of electoral votes.] It requires Trump to withdraw, which he says he's not doing, or it would require Republicans to urge a vote for him but for the electors to vote against him.”
But Hasen said it’s far more feasible that the GOP simply cuts its losses on the presidential race and turns their focus to congressional battles.
“What's likely to happen is that Trump remains on the ballot and loses badly, and Republicans pull out everything to hold the Senate and House,” he said.
Times staff writer Lisa Mascaro in Washington contributed to this report.
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