Published: Jun 05, 2012 3:49 PM EDT

MIAMI (AP) - Vice President Joe Biden urged a newly minted class of high school graduates not to believe those who say the future of the United States will not be as bright as its past, delivering a commencement speech Monday in Miami.
    
Addressing a crowd of thousands at the Miami Marlins stadium in Florida, a crucial swing state in the upcoming presidential elections, Biden urged the graduates to imagine a future filled with technological advances.
    
"Imagine the progress you will see in your lifetime," he said before going on to describe breakthroughs in science and medicine that will cure diseases and improve quality of life.
    
Political analysts said it's no surprise Biden chose South Florida as one of the three places where he will deliver commencement speeches this spring, given the state's strategic importance. Speaking to the graduates and families at Cypress Bay High School also granted him an opportunity to address two crucial voter segments: youth and minorities.
    
Cypress Bay High School is located in Weston, a community with a large Hispanic population in Broward County, which voted solidly Democratic in 2008. Susan McManus, a political science professor at the University of Southern Florida, noted that turnout among minorities in Broward County was considerably lower than usual in the 2010 elections.
    
"Obviously they don't want that to happen again," she said.
    
McManus also noted that new voters right out of high school are more likely to continue casting ballots for the same political party if the first candidate they voted for wins.
    
Many of the young graduates from Cypress Bay High School said they were inspired by the speech and that seeing Biden speak had reconfirmed their interest in voting for Obama.
    
"I really hadn't planned it out," said Sabrina Robles, 18. "But now that I've seen him speak, he's a great man."
    
Others were less impressed. Melissa Stojanov, another graduate, said she hasn't decided yet who to vote for and that the speech hadn't influenced her in either direction.
    
"He's ok," she said, declining to go into further detail.
    
The unemployment rate among youth ages 16 to 24 has declined since reaching a peak in April 2010 of nearly 20 percent. Last month, 16.1 percent of youth in that age range were unemployed, according to the Bureau of Labor Statistics.
    
In his speech, Biden described the United States as the "indispensable nation," as former Secretary of State Madeleine Albright did more than a decade before.
    
Biden said the phrase is true today because the United States is open and tolerant, and he urged the young graduates to adopt those qualities throughout their life. He said technology and the ease with which information is now spread has exposed and even amplified cultural conflicts, making acceptance and understanding all the more important.
    
"Tolerance, respect and understanding are not some obsolete old notions that don't matter anymore," he said.
    
Several young graduates said they felt optimistic about the future and agreed with Biden's notion of the United States.
    
"I believe America is coming back," said Hendrik Kruger, 17, who plans to become an FBI agent. "I believe our generation can bring America to what it used to be."

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