Report: Romney tapes phone message for Rubio’s campaign

Mitt Romney is lending Marco RubioMarco Antonio RubioOvernight Defense: Tillerson, Trump deny report of rift | Tillerson says he never considered resigning | Trump expresses 'total confidence' in secretary | Rubio asks Army to kick out West Point grad Rubio asks Army to kick out West Point grad with pro-communist posts GOP establishment doubts Bannon’s primary powers MORE his voice with a phone recording airing in the four states conducting GOP presidential contests on Tuesday.

“[Vote for] a candidate who can defeat Hillary ClintonHillary Diane Rodham ClintonChris Murphy’s profile rises with gun tragedies DNC, RNC step up cyber protections Gun proposal picks up GOP support MORE and who can make us proud,” the 2012 GOP nominee said in the message, according to The New York Times.

“If we Republicans were to choose Donald TrumpDonald John TrumpIvanka Trump pens op-ed on kindergartners learning tech Bharara, Yates tamp down expectations Mueller will bring criminal charges Overnight Cybersecurity: Equifax security employee left after breach | Lawmakers float bill to reform warrantless surveillance | Intel leaders keeping collusion probe open MORE as our nominee, I believe that the prospects for a safe and prosperous future would be greatly diminished — and I’m convinced Donald Trump would lose to Hillary Clinton.”

Romney stops short of formally endorsing Rubio’s Oval Office bid in the clip, the Times reported late Monday evening.

It also said the Florida senator’s presidential campaign is sending the call to likely voters in Idaho, Hawaii, Michigan and Mississippi.

Romney’s message may resonate most in Idaho, the Times said, where many Republican primary voters are Mormon like the 2012 GOP presidential nominee. It may additionally help Rubio in Michigan, where Romney's father, George Romney, was governor from 1963 to 1969.

Romney has become one of Trump’s fiercest critics, arguing that the billionaire’s policy stances and temperament disqualify him from the presidency.

He offered his most stinging criticism last Friday, vowing he would never vote for Trump should the real estate tycoon take the Republican presidential nomination.

Rubio, meanwhile, is scrambling to reverse his campaign’s momentum after a series of disappointing results nationwide. He won only two such events since last month, well behind Trump’s 12 and six for Sen. Ted CruzRafael (Ted) Edward CruzWhatever you think the Alabama special election means, you’re probably wrong This week: Congress gets ball rolling on tax reform Week ahead: Senators work toward deal to fix ObamaCare markets MORE (R-Texas).

Trump remains the GOP presidential front-runner nationwide, leading his rivals by nearly 16 points in the latest RealClearPolitics average of polls.