With just two weeks left before the hourglass runs out for Republicans like Florida Sen. Marco Rubio or Ohio Gov. John Kasich to show they can mount a serious challenge to Donald Trump, the question of how to take down the front-runner should they fail has made its way onto the lips of many a GOP insider. After a tour de force for Trump in Super Tuesday states, the path ahead for those rivals is doubtful at best, and some are wondering if the only truly viable option now is running a third-party candidate against him.

Such a gambit may be desperate and extreme, and many in the party think it is, but there is at least some evidence that Republicans are seriously considering its merit. Some GOP leaders, including senators, congressmen and governors, already have declared they won’t vote for Trump — no matter what — and some have even presented the strategy publicly.

“My current answer for who I would support in a hypothetical matchup between Mr. Trump and [former Secretary of State Hillary] Clinton is: Neither of them,” Sen. Ben Sasse, a Nebraska Republican, wrote in an open letter this week to Trump supporters that insisted he is not an “establishment” member of the GOP. “I sincerely hope we select one of the other GOP candidates, but if Donald Trump ends up as the GOP nominee, conservatives will need to find a third option."

The move would be risky, to be sure, but could be the only way to guarantee that the Republican Party as it is currently known isn’t subjected to four years of Trump wielding power from the White House, molding the party machine and platform through rewards given to people he likes and stonewalling those he doesn’t.

The Republican establishment, including the top leaders of Congress, Speaker of the House Paul Ryan of Wisconsin and Senate Majority Leader Mitch McConnell of Kentucky, have expressed dissatisfaction with Trump for what some see as a dangerous, open embrace for alienating rhetoric aimed at Muslims and Mexicans and for a seeming lassitude to denounce racism among his supporters. Ryan and McConnell both publicly condemned Trump Tuesday for his slow pivot to denouncing former Ku Klux Klan leader David Duke, who praised the billionaire over the weekend.

For Republicans considering taking Trump on with a third-party conservative, the concern is that the effort will alienate the base that is so energized by him or that such a Hail Mary would create a lasting schism in the party. But the gamble might be worth it, according to Hans Noel, a professor of political science at Georgetown University in Washington and author of "Political Ideologies and Political Parties in America."

“I think it does risk alienating some of those people, [but Trump supporters] are pre-alienated," Noel said, noting that Trump's voters are upset with the status quo and like him because he isn't a career politician. A third-party run is “a viable strategy if what you want is Trump to not be the president — which is not exactly a bad thing for Republicans to think — because, if Trump is the nominee and he loses, then this is a blip” in history, Noel said.

This wouldn’t be the only time in American history that something similar happened, but it certainly doesn’t happen often. While the specifics do differ, the nominations in 1912 — among Republicans — and 1948 — among Democrats — fractured their respective parties, resulting in two or three candidates originally from the same party competing against each other.

Republicans lost the general in 1912, when incumbent President William Howard Taft finished third behind ex-President Theodore Roosevelt and Democrat Woodrow Wilson, but they were able to patch their party together and win back the White House in 1920 (and nearly in 1916). Democrats had a different experience at their 1948 convention. After the party put desegregation language in the platform, much of the Mississippi and Alabama delegations alongside many other Southern delegates simply walked out and backed Strom Thurmond as a Dixiecrat candidate. President Harry Truman eventually won the general, but the split marked the beginning of the abandonment of the party by Southern white voters.

Given that history, Bruce Schulman, a professor of U.S. political history at Boston University, said it's unlikely the GOP will run a third-party candidate against Trump.

“I would imagine that the Republicans will begrudgingly get in line behind Trump unless there’s something virtually unexpected,” Schulman said.

Beyond that, the logistics of getting a third-party candidate on the ballot are prohibitive. Conservative donors have been thinking about a third-party run and have hired a GOP consulting firm, according to Politico. But the window to get a candidate on the ballot in states with the earliest deadlines like Texas and North Carolina would require that the effort start on March 15 at the latest, the day of the primaries in Florida and Ohio that could finally close the door for Rubio or Kasich if they don't win big. But even a unified effort from big donors and strategists, as opposed to the kinds of grassroots support that has hoisted Trump to the top, could fall short.

“We’re so late in the game the logistics are unfeasible,” Ford O’Connell, a Republican strategist and veteran of the 2008 presidential campaign of Sen. John McCain. “The fact is, if you run a third-party candidate against Trump, Hillary Clinton wins the White House, so if you want to spend all those millions and cut of your noses, you give away the White House and the Supreme Court.”