President William Taft, who served from 1909-1913, may have met with a tiny group of Latino activists in El Paso, Texas, Zamora said. President Dwight D. Eisenhower likely shock hands with some Mexican-American voters in a campaign visit to South Texas in 1952. "But I think no president had ever publically thanked Mexican-Americans in that manner," said Zamora.
Fifteen hours after the historic meeting, Kennedy was dead.
Band members who had played for the president the night before wept as the news unfolded. When Arroyos heard about the assassination, he told his boss at an import company he was too upset to work. Arroyos rushed to collect from friends as many photos as possible of Kennedy's visit at the Rice Hotel as he could for a future edition of a LULAC newspaper.
On Election Day 2012, analysts routinely spoke of Latinos finally awakening as a "sleeping giant" by giving Obama around 70 percent of their vote. But Ignacio Garcia said that assessment ignores how Latinos have influenced presidential elections for more than 50 years.
In 1960, for example, their overwhelming backing helped put Texas and New Mexico in Kennedy's column during the tight race against Nixon. The Republican's campaign did not have a presence in Mexican-American neighborhoods and did not have a Spanish language TV ad, unlike Kennedy, who tapped the first lady for it. Kennedy also made promises to appoint Mexican-Americans to his administration.
Johnson enjoyed support from Hispanics who campaigned for him during his landslide victory in 1964, and Mexican-Americans came out strongly for Sen. Robert F. Kennedy, D-N.Y., during the 1968 Democratic primary in California.
In 2000, then-Texas. Gov. George W. Bush, a Republican, was able to edge Democrat Al Gore, thanks in party to receiving about 40 percent of the Latino vote, according to various estimates.
"The Latino vote did not come of age the night Obama was re-elected," said Garcia. "It came of age Nov. 21, 1963."
The reason the Latino vote is attracting attention in 2012 is that Latinos are now the largest minority group in the U.S. and voter participating rates are up, Garcia said.
Voter participation for eligible Latino voters has gone from 3.7 million in 1988 to an estimated 12.5 million in 2012, according to the Pew Hispanic Center. That number could to double within two decades, the center said.
Arroyos said most of the older activists shrug off the pronouncements that Hispanics are finally influencing national elections even though his generation helped give birth to the Latino vote. Still, he said even those who are still alive and remember that Kennedy speech probably don't even know what role they played that eventually led to the voting numbers in 2012.
"I didn't know that evening was so historic," said Arroyos. "I was just happy that he dropped by and just didn't say hi."
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