Democrats have entrusted the weighty task of opening their party convention next month to the Mexican-American mayor of San Antonio, Julian Castro, a choice that shows that the road to the White House passes through the Hispanic vote.

Castro will give the keynote address on the evening of Sept. 4, kicking off the convention where President Barack Obama will accept his party's nomination for reelection in November.

It will be the first time in the history of the Democratic Party that a Latino leader has spoken in prime time at the national convention.

Castro, the mayor of the country's seventh largest city, will occupy the same place in the national political arena as Obama in 2004, when he was a candidate for the U.S. Senate.

The selection of Castro, experts say, points to the growing influence of Hispanics, who constitute the largest U.S. minority and who have steadily increased their numbers and percentage representation at all levels of government.

It is a situation where both parties win: the Democrats because they can cement their already favorable position among the Hispanic electorate, and Castro because it gives him exposure and the chance to aspire to higher office.

"Obama already has about 70 percent of the Hispanic vote, and symbolic gestures like this ... only help him to strengthen his connection" with this electoral bloc, analyst Larry Sabato told Efe on Wednesday.

"On the other hand, Castro would receive a pile of publicity on the national level and a big push for his political career," Sabato added.

Matt Bennett, the cofounder of the centrist group Third Way, said that there could be no better option, because the 37-year-old Castro is "young and full of energy," and that is "exactly the type of message that the party wants to send" to its base.

That same impression is held by John Podesta, the founder of the progressive Center for American Progress, who referred to the mayor using superlatives such as "an intelligent, effective and innovative leader."

Castro, who is in his second term after garnering 82.9 percent of the vote in 2011, will be able to add the Democratic Convention to his long list of achievements that show that - just like Obama in 2004 - he is a rising star in the Democratic Party.

A San Antonio native who was educated at Stanford University and Harvard Law School, he embodies the American Dream.

With an unhurried and deliberate manner of speech, he shares with Obama certain life experiences: both were raised by a single mother and the two men frequently emphasize in public forums that, despite its current challenges, the United States continues to be the country that rewards hard work with opportunities for success and personal achievement.

Calculations are that 12.2 million Hispanics will go to the polls on Nov. 6, and both Obama and Republican rival Mitt Romney are actively courting their votes.

In 2008, Obama received 67 percent of the Hispanic vote compared with 31 percent that went to the Republican candidate, John McCain.

Although Hispanics are disappointed by the lack of immigration reform during Obama's presidency, he leads Romney among Hispanics by 67 percent to 23 percent, according to the NBC-Wall Street Journal-Telemundo poll published last week. EFE