President John F. Kennedy was supposed to just stop by and wave hello.
Instead, a group of eager Hispanics persuaded him to come inside and speak to a packed room of Mexican-American civil rights activists. And then he persuaded his wife, first lady Jacqueline Kennedy, to address the crowd in Spanish.
It was Nov. 21, 1963. Hours later, the president was dead, his assassination overshadowing the significance of a speech that can be seen as the birth of the Hispanic vote, so instrumental in 2012 in helping re-elect the first black president, Barack Obama.
To historians, Kennedy's appearance at the Rice Ballroom in Houston was likely the first time that a president officially acknowledged Hispanics as an important voting bloc.
Though there are no plaques marking the historic occasion, the event is a touchstone for activists even if the spot where Kennedy sat and heard a band play Mexican ballads and where the crowd yelled "Viva Kennedy!" is now a refurbished ballroom in a loft apartment complex that often plays host to weddings.
"That evening ... that's where it began," said Ignacio Garcia, author of "Viva Kennedy: Mexican Americans in Search of Camelot" and a history professor at Brigham Young University. "But because very few people know about the meeting, it's like it never happened."
The surprise visit came after Mexican-Americans in Texas, New Mexico, California, Arizona, Illinois and Indiana helped Kennedy win critical swing states in 1960, thanks to an unprecedented voter registration drive in Hispanic communities. Independent "Viva Kennedy!" clubs sprang up. Sen. Dennis Chavez, New Mexico Democrat, and Texas legislator Henry B. Gonzalez of San Antonio, a future congressman, began speaking in Hispanic neighborhoods across the country and positioned themselves as the first recognizable national Hispanic political figures.
Just as in 2012, Republicans in 1960 did little to woo Hispanics to support their presidential candidate, Richard M. Nixon. Hispanics also identified with Kennedy, who was Catholic and Irish-American, a member of an ethnic group that had battled discrimination similar to what Hispanics faced in the segregated Southwest.
On Election Day in 1960, Kennedy won 85 percent of the Mexican-American vote.
But during Kennedy's first months in office, Hispanic leaders expressed dismay that the president had failed to appoint Hispanics in his administration. Chavez even openly criticized Kennedy for his lack of appointments. Other leaders embarked on a letter-writing campaign over the slow movement on civil rights.
Sensing another close election in 1964 and hoping to ease tensions, Kennedy visited Texas in November 1963. Advisers suggested that he at least pay a quick visit to Mexican-American activists at a Houston gala sponsored by the League of United Latin American Citizens, then the largest Hispanic civil rights group in the country.
"The Secret Service told us that he may stop by, but not to advertise it because it wasn't part of his official schedule," said Alexander Arroyos, 76, who was an officer in LULAC at the time. "We could spread it through word-of-mouth. No one believed us."
Then Kennedy showed up.
The president was greeted at the door by Macario Garcia, who was awarded the Medal of Honor for his service during World War II. Inside the ballroom, Kennedy and the first lady found an enthusiastic crowd of World War II veterans, civil rights advocates and future elected officials.
Kennedy spoke briefly about foreign policy in Latin America and the importance of LULAC. The first lady told the crowd in Spanish that Texas had a deep history with Hispanics. The crowd responded with chants of "Viva Kennedy!" A band played a ballad in Spanish as photographers took photos of the Kennedys and Vice President Lyndon B. Johnson and his wife, Lady Bird Johnson.
Before that moment, historians believe that no president had ever acknowledged Hispanics as a voting bloc, said Emilio Zamora, a historian at the University of Texas at Austin.
President William Howard Taft, who served from 1909 to 1913, may have met with a tiny group of Hispanic activists in El Paso, Texas, Mr. Zamora said. President Dwight D. Eisenhower likely shook hands with some Mexican-American voters in a campaign visit to South Texas in 1952. "But I think no president had ever publicly thanked Mexican-Americans in that manner," said Mr. Zamora.
Fifteen hours after the historic meeting, Kennedy was dead.