DES MOINES, Iowa — With his strong showing in the caucuses here, Marco Rubio is growing closer to consolidating the establishment wing of the Republican Party — and tightening the noose around the necks of his mainstream GOP rivals, including Jeb Bush.

Rubio’s third-place finish, top party officials, donors and strategists said on Tuesday, positioned him to take the establishment mantle and win over Republican leaders who are eager to coalesce around a single candidate and halt insurgents Donald Trump and Ted Cruz. His foes, conceding that time was growing short to demonstrate strength, spent the day in private strategy sessions where they plotted how to prevent powerful supporters from bolting.


“Marco Rubio controls his own destiny for the first time in this campaign,” said Josh Holmes, a former chief of staff to Senate Majority Leader Mitch McConnell. “If he performs in New Hampshire, it is very difficult to see how his campaign won’t quickly consolidate a lot of support.”

With the GOP hierarchy warming to Rubio, the squeeze is suddenly on struggling establishment contenders Chris Christie, John Kasich and Bush, who must convince party higher-ups that they have a reason to continue on. On Tuesday morning, top Bush donors and finance officials held two conference calls to discuss the path forward. On one, according to one participant, there was an acknowledgement of the campaign’s increasingly long odds and an agreement that, barring a strong Bush showing in New Hampshire, many Bush donors would soon bolt to Rubio.

“Have you ever heard the phrase ‘rattle of death'?” the participant said, describing the mood on both calls.

After getting crushed in the Iowa caucuses, Bush suffered another blow on Tuesday, when South Carolina Sen. Tim Scott announced that he was endorsing Rubio. While some Bush aides said they were not particularly surprised by Scott’s decision, they acknowledged disappointment. The Bush campaign had aggressively courted Scott, the only black Republican in the Senate and a key elected official in an early primary state. Bush himself had personally appealed to Scott for his support, one Bush aide said.

Two Bush aides, speaking on the condition of anonymity, said there was growing concern that Rubio was on the verge of getting a wave of endorsements from senators, state party chairs and influential party officials and donors — a scenario, they conceded, that would give Rubio an aura of invincibility in the fight for support in the establishment lane. For Bush to remain viable, they said, he would need to outperform Rubio in New Hampshire, a state that the former Florida governor has made a cornerstone of his primary campaign. Many top GOP officials see the state as the last, best chance for Rubio’s establishment rivals to stop him.

“The New Hampshire primary should make the Republican picture a lot clearer,” said Steve Duprey, an influential Republican National Committeeman from New Hampshire who is neutral in the contest. “If Sen. Rubio finishes strongly and substantially ahead of other contenders running in that lane, I think this would lead to a surge in support for him.”

Behind the scenes, Rubio’s team is stoking the flames. During a Tuesday conference call with top Rubio campaign officials and donors, deputy campaign manager Rich Beeson suggested it was time for other mainstream candidates to drop out. “Any candidate other than the top three finishers in Iowa are dreaming right now and shouldn’t stay in,” one person on the call quoted Beeson as saying.

For Bush, though, the question of whether to stand down is a complicated one. Of Rubio’s three mainstream rivals, he has the greatest ability to compete well into the primary calendar. Unlike Kasich and Christie, the former governor has established a formidable national political infrastructure. Bush also has a cash-flush super PAC, Right to Rise, that reported over the weekend that it had over $50 million cash on hand — a substantial total that far outpaces its counterparts.

While many in the GOP express private concern about the prospect of an expensive and drawn-out battle between Bush and Rubio that could divide support and hand primary victories to Trump and Cruz, the Bush campaign insists it is looking to New Hampshire and beyond. On Monday evening, the campaign circulated an internal memo arguing that Iowa would have little impact on the outcome of the primary and that New Hampshire and South Carolina represented better political terrain for Bush.

“The real race for the nomination begins on February 9th in New Hampshire,” the memo said. “It will set the race going forward.”

A Bush spokesman, Tim Miller, argued that, unlike others, Bush had no reason to stand down anytime soon. “Christie and Kasich have no organization or appeal after New Hampshire, whereas Jeb is third in South Carolina and has the best team on the ground for a caucus in Nevada,” he said.

Mel Martinez, a former Florida senator and Republican National Committee chairman who is supporting Bush, said he envisioned a primary stretching into at least March, when the two would face off against each other in their home state of Florida.

“After Iowa and New Hampshire it will come down to Marco and Jeb in the so-called establishment lane,” Martinez said. “They will collide in Florida, if not sooner.”

For all the uncertainty about how the coming weeks will play out, though, many in the Republican Party’s battered and bruised top ranks called Monday’s result an encouraging development. After months of mounting alarm that Trump and Cruz might be unstoppable, they now see a path to unite the mainstream wing of the party and defeat them.

“Rubio delivered an impressive performance, and we’ll see how that translates to the contests ahead,” said Steven Law, president of American Crossroads, a conservative outside group with ties to former George W. Bush aide Karl Rove. “The larger takeaway from last night was that Donald Trump is not invincible, Hillary Clinton is not inevitable, and we still have an opportunity to nominate a truly competitive conservative for the general election.”

