Miami voters have their own rhythm, the Spanish-language TV spot says, suggesting only one Republican presidential candidate can keep up. The narrator, rolling his Rs, delivers the Cuban-American name with brio: "Marco Rubio."

"Orgulloso hijo de Miami," the voice continues over aerial shots of Florida's Sun Life Stadium and the Hialeah fountain terrace, hailing the Republican presidential candidate as "the proud son" of this sunny, vibrant city on Florida's south tip.

In the ad, Latin-tinged music plays over the footage. It's the sound of Little Havana. But it's also the sound of money — lots of it.

The funds are flowing from as much as $12 million US in political ads days before Tuesday's crucial Florida Republican primary, according to Kantar Media, a firm that tracks campaign ad spending.

Courting the southern part of this swing state's largely Republican-leaning Cubano voters is a necessary play in the Sunshine State, where 10 media markets mean ad buyers have some expansive — and expensive — ground to cover.

In Florida alone, the Rubio-aligned Conservative Solutions group has aired more than 2,300 commercials since Super Tuesday, according to Kantar Media's campaign analysis group. The PAC was expected to shell out $9.6 US million on radio and TV before March 15.

Gilbert and Michelle Santana

Gilbert Santana, pictured with his wife Michelle and son at Versailles restaurant in Miami's Little Havana neighbourhood, says he has seen the Spanish-language ads supporting local Republican presidential hopeful Marco Rubio. (Matt Kwong/CBC)

"The onslaught has begun," says Susan MacManus, who lectures on media and politics at the University of South Florida. "It's in full force and people are getting saturated with ads."

The ad blitz is a pricey indicator of how desperately outside political groups want to keep Rubio in the race for the Republican Party nomination.

Of the five states holding Republican contests on March 15, Florida's 99 delegates presents the biggest bounty for the start of the high-stakes winner-take-all primaries.

But the diversity of the delegate-rich state's voting population means ad buys need to be strategic.

"Florida is one of those states where money matters a lot, and if you want to advertise in Florida, you're spending at least $1 million a week," says Kevin Wagner, who teaches American politics at Florida Atlantic University in Boca Raton.

Wagner divides the state into quadrants, with Northern Florida and the Panhandle sharing voting characteristics of "a traditionally southern state," Palm Beach and Eastern Dade having a moderate "northeastern" or urban base, and South Florida having the topsy-turvy quirk of feeling more like a liberal northern state.

The Tampa and Orlando media markets, occupying both ends of the politically strategic "I-4 corridor" bisecting the swing state, makes up a fourth chunk. This quadrant serves 44 per cent of Florida's registered voters but is far from homogeneous.

Attacking Rubio on 'Big Sugar'

The region is evenly divided between Democrats and Republicans, with a smattering of independents. For ad buyers, this patchwork diversity poses a nightmare.

"We have every demographic group here in big numbers," says Robert Watson, a professor of American Studies at Lynn University. "We have one of the nation's largest Jewish populations, black populations, gays, Latinos, senior citizens, veterans, they're all here in Florida."

One ad by Keep the Promise 1, a PAC backing Texas Senator Ted Cruz, goes specifically after Rubio for his relationships with "Big Sugar," a topic that may only touch a nerve among Everglades-area residents and environmentalists who view sugar production as environmentally destructive.

Watch enough cable news or Spanish TV in Florida this weekend, and it's easy to catch a round of pro-Rubio commercials, or ads aimed at stopping front-runner Donald Trump.  

Groups opposing Trump are hedging on Florida as an eleventh-hour drive to knock him off his pedestal, with a string of attack ads doing the pushing.

According to reports, the Super PAC American Future Fund pumped $1.75 million US to oppose Trump in Florida, casting him as a draft dodger, and the anti-tax PAC Club For Growth committed another $1 million US solely on another anti-Trump effort.

Breakfast at Versailles in Miami

Customers eat breakfast at Versailles Cuban restaurant in Miami's Little Havana district. The restaurant is known as a popular meeting place for Cuban-Americans to talk politics for hours. (Matt Kwong/CBC)

Rubio's camp is hoping big ad spending will shave points off Trump's dominance.

According to a Real Clear Politics aggregate, Ted Cruz is polling in third place with 18.3 per cent, behind Rubio's 24.8 per cent and Trump's 40.6 per cent.

At Little Havana's Versailles restaurant, ground zero for Cuban-American politicos, a breakfast crowd dining on eggs and Cuban toast says the ads only clarify what they already knew about one candidate.

'You offend all of us'

From table to table, the recurring answer among undecided voters is: "Not Trump."

Gilbert Santana, who has seen the Spanish-language ads supporting Rubio, says he isn't completely sold on the candidate. But he articulates a problem that others at Versailles repeat about Trump.

"He offended Mexicans. I'm Puerto Rican. But you offend one nationality, you offend all of us," he says.

Old Men Of Versailles

In this photo made Nov. 30, 2010, the late afternoon sun shines behind the sign in front of Miami's Versailles restaurant. Miami is the de facto capital of Cuban exiles, and Versailles is their prime meeting spot. The old men call themselves La Pena del Versailles (The Club of Versailles). (AP Photo/J Pat Carter) (J Pat Carter/Associated Press)

In at least that sense, the "stop Trump" movement might have the desired effect.

"A vote for Cruz or Kasich is a vote for Trump," one common ad from the Rubio-aligned Conservative Solution political action committee warns, attacking the billionaire businessman's leadership.

The American Future fund, a separate PAC also backing Rubio, has been running a highlight reel of Trump swearing on stage. "Offensive. Out of Control. America Can do Better," a text block reads.

Cuban-American candidates 'a point of pride'

Even if the ads are effective, blunting the Trump effect may not deliver Florida to Rubio.

Over mud-thick Cuban espressos, Sergio Cabrera says he's seen the Spanish-language ads for Rubio and remains unconvinced about the Florida senator's viability.

Fred Bracero

Fred Bracero, 36, playing beach volleyball on Miami Beach, says he's dismayed by the negative tone of the Republican attack ads airing in Florida ahead of Tuesday's primary. (Matt Kwong/CBC)

"I'm not swayed by ads," says the 62-year-old, who left Cuba as a refugee at the age of seven. "After growing up in a Communist Socialist country, I'm concerned about crony capitalism but also worried about moving towards strong socialist policies."

Instead, Cabrera will vote for Cruz, a candidate who stands very little chance of taking Florida.

Carbrera's dining companion, also a Cruz supporter, notes it's "a point of pride" that two of four remaining Republican candidates are Cuban-Americans.

"We share the same story. I was born here but my parents left Cuba," he says. "But I don't vote for a Cuban-American; I vote for a candidate."

Sergio Cabrera

'I'm not swayed by ads,' says Sergio Cabrera (pictured on the right). Cabrera, who left Cuba at age seven, says he will vote for Texas Senator Ted Cruz instead of Florida Senator Marco Rubio. (Matt Kwong/CBC)

This weekend's tsunami of ads may air too late for many Floridians, as absentee and early voting already began at the beginning of the month.

And there's another potential problem — a generational one.

Fewer people are watching television than ever before. Spring Breakers who intend to vote in Tuesday's primary say they hadn't seen a single attack ad. Asked how they keep informed, millennial voters drinking oversized frozen beverages by the beach say they stream debates or follow coverage online, and rarely on TV.

"We're cord-cutters," says one young woman in a bikini, walking with friends along Ocean Drive. "But I'm so sorry. I'm too drunk to talk politics right now."