Don't mess with Daddy Yankee.

That's the warning from John McCain's campaign after The Politico.com quoted a Democratic Party source saying Daddy Yankee approached Barack Obama's campaign earlier this year offering an endorsement but did not pass the campaign's vetting process and was rejected because of his racy lyrics and an assault charge against him.

The Latino singer, whose real name is Ramon Ayala, endorsed McCain on Monday.

A McCain aide responded that the Obama camp ought to be careful what fights it chooses to pick.

"I would say they shouldn't mess with Daddy Yankee," the aide said. "They have their own rappers that support him and the truth is (Daddy Yankee)'s incredibly popular in the Hispanic community and across the country, and, they need to be able, they need to take, they need to take it easy on the Yankee."

Yankee's publicist Mayna Nevarez also called the Obama camp's claim "completely, completely false."

"I have no idea where this rumor came from," Nevarez told FOX News. "The musician and his camp never approached or in anyway asked the Obama campaign about a possible endorsement."

Nevarez said the Daddy Yankee-McCain relationship goes back two or three years to when the Reggaeton megastar and presumptive Republican presidential nominee met at an event to note Time magazine's 100 most influential people.

They

arrived at the location at the same time and started a conversation.

McCain, a boxing fanatic, and Ayala, a former boxer, immediately hit it

off.

FOX News' Serafin Gomez contributed to this report.