Donald Trump could end up destroying the Republican Party if he were to become the 2016 presidential nominee, famed strategist Karl Rove is warning party leaders.

With Trump rolling in the first few states to vote, and polls showing him with significant leads in other upcoming contests, it appears difficult to stop his momentum toward the nomination. He has generated the most enthusiasm among voters, many of whom are tired of the same establishment candidates.

That now has many within the Republican establishment worried, as evidenced by Karl Rove’s address to major donors earlier this month. Rove, who led George W. Bush’s winning campaigns, implored those in attendance that a Donald Trump candidacy would be a total disaster for the party, squandering the party’s chance to take back the White House after Barack Obama leaves office.

The speech inspired some to take action, according to a report by the New York Times.

“At a meeting of Republican governors the next morning, Paul R. LePage of Maine called for action. Seated at a long boardroom table at the Willard Hotel, he erupted in frustration over the state of the 2016 race, saying Mr. Trump’s nomination would deeply wound the Republican Party. Mr. LePage urged the governors to draft an open letter “to the people,” disavowing Mr. Trump and his divisive brand of politics. “The suggestion was not taken up. Since then, Mr. Trump has only gotten stronger, winning two more state contests and collecting the endorsement of Gov. Chris Christie of New Jersey.”

“The one person that Hillary and Bill Clinton do not want to see on that stage is…#DonaldTrump.” - @ChrisChristiehttps://t.co/Tc7uSMuqRN — Fox News (@FoxNews) February 26, 2016

But in order for the party to snuff out Donald Trump’s campaign, the party needs to be able to coalesce behind one candidate, the New York Times report noted. That has not worked so far, with Ohio Gov. John Kasich refusing to leave the race despite some not-so-gentle suggestions from Mitt Romney. Other candidates have taken turns attacking one another, making it difficult for the party to come together.

Now that Donald Trump has the endorsement of former candidate and New Jersey Governor Chris Christie, the plans to knock off his campaign have grown even more difficult. That has led to deep fear within the party, with two strategists telling the New York Times that a Trump nomination would mean not only Democrats taking the White House, but also Republicans losing the Senate, competitive governors races and moderate Congressional seats.

Other powerful figures have attempted to undercut Trump’s campaign. Michael Hayden, former head of the NSA and CIA, said Trump has made unlawful campaign promises that could lead U.S. Armed Forces to disobey his orders. Trump has called for terrorist suspects to be waterboarded and said he would target families of terrorists, which is banned by the Geneva Conventions.

“If he were to order that once in government, the American armed forces would refuse to act,” Hayden said Friday during an appearance on Real Time with Bill Maher (via The Huffington Post). “You are required not to follow an unlawful order that would be in violation of all the international laws of armed conflict.”

Donald Trump must be stopped before it’s too late https://t.co/Lypn0rDqdR pic.twitter.com/FpzFSH7ABj — The Economist (@TheEconomist) February 28, 2016

The Economist is also coming out against Donald Trump, noting that 46 percent of Americans have a “very unfavorable” view of him which gives him a very light chance of winning the presidency.

“The things Mr Trump has said in this campaign make him unworthy of leading one of the world’s great political parties, let alone America. One way to judge politicians is by whether they appeal to our better natures: Mr Trump has prospered by inciting hatred and violence. He is so unpredictable that the thought of him anywhere near high office is terrifying. He must be stopped.”

Though the Republican Party, from Karl Rove down to major donors, is working against Donald Trump, it appears the efforts may be futile. With the series of wins he is expected to get on Super Tuesday, Trump could all but lock up the nomination.

[Image via Instagram/Donald Trump]