John McCain on Monday issued a new ad in Spanish, coinciding with Cinco de Mayo and the Republican presidential candidate's effort to attract Hispanic voters.

Meanwhile, Barack Obama, who also has tried to pull Democratic Latino voters from Hillary Clinton this primary season, also sent his well-wishes.

McCain, who announced that he will attend the annual convention of the National Council of La Raza in San Diego on July 14, said Cinco de Mayo is a chance for Mexico to celebrate its path to freedom.

"On this day in 1862, a small group of Mexican troops overcame overwhelming force to win the Battle of Puebla. Today, we join together to remember the sacrifice that these Mexican patriots endured, as well as the struggles of all those around the world striving for freedom. We recognize as well the important friendship that exists between our country and Mexico, and celebrate the many contributions Mexican-Americans have made to our society, culture, security and economy," he said.

Obama said that "while Mexico's cultural traditions are an important part of who we are as Americans, the American dream is still out of reach for too many Latinos."

"our broken immigration system works for neither the immigrant families who are being torn apart nor the workers who are concerned about unfair competition, which is why we need to pass comprehensive immigration reform once and for all. So while I hope that all Americans are enjoying this Cinco de Mayo, I also hope that when the celebrations come to an end, we'll take up the cause of coming together as Americans to solve our common challenges and put the American dream within reach for every family in this country," he said.

In 2006 McCain sponsored legislation along with Democratic Sen. Ted Kennedy to reform immigration laws and allow illegals to apply for legal residency retroactive to their arrival. Conservatives around the nation criticized McCain for the bill, which they said was too lenient against lawbreakers.

McCain has said since then that he learned the lesson that focusing on border security is primary, but on Monday he argued that the focus on illegal immigration during the Republican primary season has harmed his party's image among Hispanics.

Speaking to reporters in Phoenix, McCain said Hispanic citizens want America's borders secured and illegal immigrants to be treated humanely.

He added that low-income Hispanic citizens are vulnerable to losing their jobs to the lower wages accepted by illegal immigrants.

On the subject of broader immigration policies, McCain said local governments would not have had to take on immigration problems had the federal government overhauled the country's immigration policies.

FOX News' Mosheh Oinounou and The Associated Press contributed to this report.