Mike Rounds got the call from Marco Rubio’s campaign within hours of his big third-place finish in Iowa: Would the South Dakota senator consider an endorsement now that Rounds’ pick, Mike Huckabee, dropped out?

“I told [the Rubio surrogate], ‘We’ll be happy to visit with you. … Marco is very qualified, he’s got a huge amount of energy, and I think his values are the right values.’”


But Rounds wasn’t ready to commit; he wanted to speak to Huckabee first. Ditto for Arkansas Sen. John Boozman, another Huckabee backer on Capitol Hill.

After the Senate GOP’s persona non grata, Ted Cruz, notched a commanding win in Iowa, there was growing sentiment Tuesday among Republican senators — a bellwether of the GOP establishment — that they need to coalesce behind a single candidate in the nominating contest to beat back Cruz and Donald Trump. But if Rubio was hoping for a stampede to his corner following South Carolina Sen. Tim Scott’s key endorsement, it did not materialize on Tuesday.

No senators defected to Rubio from other mainstream Republican hopefuls. Sen. Rob Portman (R-Ohio), a John Kasich backer, says he isn’t going anywhere. Jeb Bush supporter Orrin Hatch of Utah is convinced that his man, whose backing on Capitol Hill slightly outpaces Rubio’s, will catch lightning in New Hampshire after a dismal finish in Iowa.

And former presidential candidate Lindsey Graham isn’t just sticking by Jeb Bush — the South Carolina senator took to the airwaves Tuesday to rip Rubio for veering “hard right” on immigration and social issues.

The reluctance means that Republicans who’ve been clamoring for a consensus candidate to take on Cruz or Donald Trump will have to wait a little longer — probably at least until after New Hampshire, where Rubio needs to elbow aside the likes of Chris Christie, Bush and Kasich to maintain his momentum.

The prolonged establishment candidate pileup “could be problematic,” said Sen. Dean Heller (R-Nev.), a Bush supporter who could bring political heft to Rubio in Nevada. But “I don’t think at this point Rubio has a claim for” support from the bulk of the Senate GOP caucus.

“In other words, he did well yesterday, and I certainly think he did a great job yesterday — but let’s see what happens in New Hampshire,” Heller said. “If Rubio does as well in New Hampshire, then I think there will be new discussions.”

Senior Republicans are relying on New Hampshire to cull the herd and increase pressure on fence-sitting senators. But the endorsement picture is too messy, they say, with so many potential candidates left in the field that uniting behind one would cause a lot of hurt feelings and recriminations.

A rush of lawmakers into Rubio's camp might well come if he pulls off an encore performance in New Hampshire. Scott was heavily courted, and his move to Rubio might be the most important lawmaker endorsement of the GOP primary so far. POLITICO reported Wednesday that Sen. Pat Toomey, facing a tough reelection campaign in the general election battleground of Pennsylvania, is planning to endorse Rubio.

And despite the stagnation among senators, Rubio's campaign Wednesday bagged the endorsements of Arkansas Reps. Rick Crawford and Steve Womack, as well as Lt. Gov. Tim Griffin, a former House member.

Rubio backers are prodding rival candidates to concede they have no chance of catching him and drop out, while at the same time playing down expectations.

“Folks from New Hampshire aren’t necessarily into being told what to do, so my endorsement has more to do with South Carolina than anyplace else. But I do believe we’ll see more senators” endorse Rubio, Scott said in an interview Tuesday.

Sen. Kelly Ayotte, New Hampshire’s top Republican, says she won’t endorse or even appear with candidates around her state over the next week. Sen. John McCain, who used the state to propel his two presidential campaigns (though he lost to Barack Obama there in the 2008 general election), said he’s staying out after backing Graham.

Hawkish Sen. Tom Cotton of Arkansas, the youngest senator, has no plans to endorse; Huckabee’s withdrawal could have liberated Cotton to come off the sidelines. Sen. Mike Lee of Utah is “not a fan” of Trump and speaks fondly of both Cruz and Rubio, but he isn’t yet planning to insert himself into the race, either, an aide said.

It’s not that any one endorsement will put Rubio over the top. But a rush of support on the heels of Rubio’s top tier performance would mean “validating the momentum” of the first-term senator’s campaign, said Sen. Cory Gardner (R-Colo.).

“How much louder do the quiet rumblings for Rubio become? Because over the past several months since I endorsed Rubio, a lot of people come up and say, ‘Thanks for doing this. Thanks for going to Iowa for Rubio,’” Gardner said, “Does that become a public conversation and turn into an endorsement?”

The answer in the immediate aftermath is: not yet. On Tuesday, the friendly talk for Rubio continued in top circles of Republican politics: They say he’s the guy who can go the distance against Cruz’s organization and fundraising, and the best face for the GOP to put forward to beat Hillary Clinton. He’s also actually nice to his colleagues, a bright contrast to Cruz.

“Marco and I have very similar backgrounds,” said Sen. Thom Tillis (R-N.C.), who is also a former state House speaker. “He does a great job interacting with the conference, [in comparison to] the other senators running.”

But an outpouring of support isn’t yet in the cards. Perhaps, senators said, not until after the South Carolina primary on Feb. 20.

“A lot of people are waiting to see what New Hampshire deals,” said Sen. John Thune (R-S.D.), No. 3 on the leadership ladder. “A lot of candidates running in that same lane are going to try to make their case there. It’s going to be a natural winnowing process; I think it’s going to run its course.”

Thune’s been hearing from the Rubio and Bush campaigns. Those two camps have been in a slugfest on Capitol Hill for endorsements, with Bush leaning on his family connections and Rubio trying to recruit more junior senators like Rounds. They are deadlocked at five senatorial endorsements each, and it’s likely to stay close until Bush drops out.

“He still got one delegate,” Hatch said of Bush, searching for a silver lining from Monday.

This year, in particular, is a tough sell with so many GOP senators looking at difficult reelection campaigns and cautious about making an endorsement that could come back to haunt them later. Republicans are defending 24 seats this fall, which means a lot of cold feet.

“I learned a long time ago that if you start endorsing people when you’re up [for reelection] yourself, to do so early would be stupid,” said Sen. Johnny Isakson of Georgia, who is up for reelection this year and has steered clear of the nomination skirmish.

With an extra spring in its step after Iowa, Rubio’s campaign is now casting the run-up to New Hampshire as a dire choice: Either join with Rubio or allow Cruz or Trump to win the nomination, as Rubio spokesman Alex Conant put it on Monday night. But the message hasn’t gotten through to many of his colleagues on Capitol Hill yet.

“I’m uncommitted,” said Sen. Shelley Moore Capito of West Virginia, who meets regularly with GOP leaders. “And I’m staying that way.”

