Media playback is unsupported on your device Media caption Romney tells US Spanish-language broadcaster Univision the US will never carry-out mass deportations of illegal immigrants - in English

President Barack Obama and Republican challenger Mitt Romney hope throwing a little Spanish into their campaign pitches will help them win coveted Latino voters. But neither are fluent in the language.

This summer, a Cuban-American radio presenter in Florida asked Mitt Romney what his favourite types of fruit are.

"I am a big fan of mango, papaya, and guava," Mr Romney replied.

The hosts could not suppress their laughter.

It may not strike you as particularly funny that Mr Romney said he liked papaya, but "papaya" is Cuban slang for vagina.

Now, come on. Let's be mature and fair here.

Who, besides a Cuban or Cuban-American, would know that?

But that was not Mr Romney's only Spanish slip-up.

She said what?

His most notorious came five years ago during an impassioned anti-Castro speech in Miami, Florida.

Media playback is unsupported on your device Media caption 'Viva Kennedy' political advert

"At the end of speech, Mr Romney had the crowd fired up," recalls Joe Garcia, a Cuban-American Democrat in Miami.

"And he ended, 'Patria o Muerte, Venceremos — the nation or death we shall win,' which is the closing line of all of Fidel Castro's speeches.

"It's a great line. Unfortunately for Romney it was the wrong line in this crowd."

Last week, Mr Romney and Mr Obama made another push for Hispanic votes, as the race enters its final stretch.

On Wednesday and Thursday, the candidates spoke at a forum in Miami broadcast by Univision, a large Spanish-language television network.

Mr Romney spoke in English, and whatever problems he has had with Spanish in the past, he was not alone.

In 2008, Secretary of State Hillary Clinton, then a Democratic presidential candidate, told a crowd, "Si, se pueda" (yes, we can).

She meant to say "Si, se puede", instead of "Si, se pueda".

The error was not a huge deal. But the slogan is among the most famous American political phrases in Spanish, popularised by Cesar Chavez in the 1960s.

Image caption Romney's father George, shown here with Mitt and mother Lenore in 1962, was born in Mexico

Then in 2007, former Republican House Speaker and presidential candidate Newt Gingrich issued a Spanish-language YouTube apology for having earlier implied the language was a "ghetto" tongue.

His Spanish was grammatically correct, but spoken in what the Washington Post called "a terminally Anglo accent".

In Denver, Colorado, I ask a couple of Spanish-speaking Obama voters how much it really matters whether an English-speaking politician has a bad accent, messes up a few words, or otherwise mangles Spanish.

Maria Young, who hails from Mexico, says she will award "a couple of brownie points".

"At least they tried," she says.

Martha Caban, from Puerto Rico, agrees: "At least they're honouring and respecting us and trying to do something to connect with us."

And what if they really, really mess it up like Romney did in Miami, quoting Fidel Castro to a group of Cuban-American voters?

"It will not matter," Ms Young says. "I am used to bad translations."

Risk of offence

But Christine Marquez-Hudson of the Mi Casa Resource Center in Denver, an advocacy and support organisation for Latino families, says broken Spanish from politicians who do not speak the language comes across as patronising.

"El Bloombito" In August 2011, New Yorker Rachel Figueroa-Levin created a parody Twitter account that mocked New York City Mayor Michael Bloomberg's attempts to speak in Spanish. Here are some of "Miguel Bloombito's" greatest hits: "Ay Ay Ay todos things are mucho wet"

"Todayo yo soy will annouñce el end de el programo del stopo y frisko. (Feliz Aprilfoolsvidad!)"

"Esta un grande misunderstanding. Yo only spy on los muslimiños por que yo necesito to know el besto carto de falafel."

"El #OWS parko de Zuccotti esta open, pero los following items es prohibito: tentos, pillowados, blanketos, speakeros, cameras, y lawyeros"

"When someone comes out who has absolutely no personal connection and says, 'Hola, bienvenido', and they say it in a really terrible accent, I think it can be offensive," she says.

But Ms Marquez-Hudson doesn't see this from either Mr Obama or Mr Romney. And she appreciates when Mr Obama uses his favourite Spanish phrase, "Si, se puede."

"The thing about Obama is that he was a community organizer, and 'si, se puede' is a community organising chant," she says. "That's the connection for me."

Presidential candidates and their surrogates have been trying Spanish in adverts as far back as the 1960's.

President John F Kennedy reached out to Latino voters with a Viva Kennedy campaign. His wife, Jackie, appeared in an advertisement warning of the dangers of communism, in passable Spanish with a decent accent.

'Apologise ahead of time'

President George W Bush won applause for speaking Spanish, though many also made fun of his Texas accent.

Image caption Obama joined the Univision forum on Thursday, defending his own record on immigration

I asked Diane McGreal of language-training company Berlitz whether a candidate should try a little Spanish even if it meant risking ridicule.

"I would inoculate the audience," says Ms McGreal, who directs the company's global leadership training programme.

"I would start out by saying, I want to apologise for any mistakes that I make and then say a few words.

"And then the next step would be to ask their permission to continue in English, to say it's important that the message I get across is clear and understood."

Another way to make absolutely certain the Spanish is correct: pre-record the message.

"Soy Mitt Romney y apruebo este mensaje," Romney flawlessly ends his Spanish-language adverts.

Listen to more on this story at PRI's The World, a co-production of the BBC World Service, Public Radio International, and WGBH in Boston