By Kevin Liptak, CNN
TAMPA (CNN) -- Sen. Marco Rubio's convention speech Thursday introducing Mitt Romney offered voters a look at one of the Republican Party's fastest-rising stars, and brought to the fore what the conservative movement hopes its future will look like.
"I watched my first convention in 1980 with my grandfather," Rubio began, placing a date on the generational shift that he and Romney's running mate Paul Ryan represent for the GOP.
Rubio, who at 41 is a year younger than Ryan, joins the Wisconsin congressman as a young face in the party whose supporters have skewed older in the past several elections. Rubio also brings diversity to the Republican stage at a moment when Romney faces a nearly 30-point deficit among Latino voters.
Rubio used his Cuban immigrant parents' story as his version of the American Dream.
"My Dad used to tell us, 'En este pais, ustedes van a poder lograr todas las cosas que nosotros no pudimos:' In this country, you will be able to accomplish all the things we never could," he said.
Rubio's remarks in Spanish spoke to the larger theme of his optimistic address: that things are possible in America that aren't possible elsewhere.
"We're special because dreams that are impossible anywhere else come true here," Rubio said.
Elected to represent Florida in the U.S. Senate in 2010, Rubio rode a wave of tea party and grassroots support to nab the GOP Senate nomination away from the sitting GOP Gov. Charlie Crist, who had the backing of the party's establishment and started the race leading in the polls.
Rubio endorsed Romney in March, toward the end of the GOP primary contests, and has since become an effective surrogate for the GOP nominee, attacking President Barack Obama for failing to improve a stalled economy and touting Romney as a candidate with the experience to turn things around.
Rubio made a few mentions of Obama in his remarks, but the heart of his speech was in the detailed description he offered of his parents' journey from Cuba to America, and his own views of how American exceptionalism made that journey possible.
"In America we are all just a generation or two removed from someone who made our future the purpose of their lives," Rubio said. "America is the story of everyday people who did extraordinary things. A story woven deep into the fabric of our society."
"Their stories may never be famous, but in the lives they lived, you find the living essence of America's greatness," he continued.
The story of immigrant parents or rising from humble beginnings has been a consistent theme through the convention as speakers told their stories. Romney advisers have made a concerted effort to improve his standing with middle class voters, where polls show voters think Obama can better relate to them and understand their struggles.
Rubio also vouched for Romney's character, saying the Republican candidate's myriad roles in life show who Romney is as a person.
"You've heard for a long time now about Mitt Romney's success in business," the Florida Republican said. "He's a devoted husband, father, and grandfather. A generous member of his community and church. And a role model for younger Americans like myself."
In making his case for Romney, Rubio provided a pro-immigration voice for a party that has struggled in adopting a policy that appeals to Latinos.
Romney himself has maintained a bumpy track record speaking on immigration, including his proposal of "self-deportation" that emerged at a CNN debate during the primaries.
Rubio sought to soften the candidate's record on Thursday by harking back to Mitt Romney's father George and his story of successful immigration.
"His family came to America to escape revolution," Rubio said of the elder Romney, who was born in Mexico to Mormon parents and, after returning in America, became the head of American Motors and governor of Michigan and made his own bid for the Republican presidential nomination.
"They struggled through poverty and the Great Depression," Rubio said of Romney's family. "And yet he rose to be an admired businessman, and public servant. And in November, his son, Mitt Romney, will be elected president of the United States."
Rubio was widely speculated to be a potential choice for Romney's running mate, though Rubio himself denied wanting to take on that role. Others, including former Florida Gov. Jeb Bush, touted Rubio's qualifications and said he would make a great pick.
Earlier this week, "The Daily Show" host Jon Stewart asked Rubio if Romney's campaign ever asked, "Hey, charisma boy, take it down a notch."
"The only thing they've asked me to do is introduce the governor," Rubio told Stewart. "They gave me 15 minutes to say anything I want."
Those 15 minutes Thursday provided Rubio, and the type of Republican he represents, a very visible place on his party's biggest night.