Though campaign officials insist Rubio has no plans to quit and expects to win the Florida primary next week, some
Recent polling suggests Trump leads Rubio 40.7% to 23.7% in Florida, according to aggregators at RealClear Politics. Cruz is third at 17.2%.
Donors, particularly more recent converts to Team Rubio who crossed over from former Florida Gov. Jeb Bush's camp, are holding onto their wallets until next week's primary.
But many also see little reason for Rubio to drop out before then.
"It's Florida or bust," said Nick Iarossi, a prominent Rubio fundraiser in Tallahassee. "We've already invested millions of dollars, thousands of man hours. Why get out six days before?"
Rob Stutzman, a GOP operative in Sacramento who was backing Bush and is now fundraising for Rubio, said the campaign is "fully invested, they're fully committed to Florida, and, frankly, they shouldn't stop before then, before the Florida vote."
"Obviously the results of the last two weeks are troubling," he added. "We'll let Florida speak for itself. Home states perform uniquely."
Rubio's team has consistently dismissed reports of hand-wringing and denied there are any conversations about dropping out. "Nobody on the campaign is discussing this," spokesman Alex Conant said.
The campaign continues to predict that Rubio will win his home state, noting that absentee ballots are breaking for the Florida senator.
They are also counting on strong support from the Latino community, including many Puerto Rican transplants who have fled the island's economic problems and registering to vote in Florida. Puerto Rico was one of two primaries that Rubio has won so far.
Including his other victory, in the Minnesota caucuses, Rubio has a total of 151 delegates, compared with 458 for Trump and 359 for Cruz. Ohio Gov.
But even if Rubio wins Florida's 99 delegates in the winner-take-all contest, he will remain far behind the front-runners.
Rubio's campaign had largely abandoned Tuesday's contests in Michigan, Mississippi, Idaho and Hawaii, marshaling all its manpower and resources in the Sunshine State. He plans to campaign there nonstop until Tuesday.
"It was always going to be a rough two weeks," said a Rubio backer granted anonymity to discuss the situation, "but the focus was always going to be on Florida and needs to remain that way."
Bowing out now might avert what could be an embarrassing political defeat for Rubio in his home state.
But his supporters argue that even if he dropped out before the Florida primary, it probably would only help Trump win the state, not Cruz.
They also questioned whether a loss at home would damage Rubio's political brand.
At 44, he has often been mentioned as a possible candidate for Florida governor. His Senate term expires in January, and he is not seeking reelection.
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