Rubio said the opportunity to succeed "isn't bestowed on us from Washington. It comes from a vibrant free economy where people can risk their own money to open a business."
Rubio, considered a potential 2016 GOP presidential candidate, said his parents immigrated to the United States from Cuba to improve their lives and give their children a better one.
"They made it to the middle class," Rubio said. "I didn't inherit any money from them. But I inherited something far better -- the real opportunity to accomplish my dreams."
While agreeing with Obama on some issues, Rubio offered a conservative alternative that flowed from a premise of smaller government.
Rubio said he lives in the same-working class neighborhood where he grew up.
"My neighbors aren't millionaires," he said. "They're retirees who depend on Social Security and Medicare. They're workers who have to get up early tomorrow morning and go to work to pay the bills. They're immigrants, who came here because they were stuck in poverty in countries where the government dominated the economy.
"So Mr. President, I don't oppose your plans because I want to protect the rich," Rubio said. "I oppose your plans because I want to protect my neighbors."
Obama believes free enterprise is "the cause of our problems," Rubio said.
The president believes "economic downturn happened because our government didn't tax enough, spend enough and control enough," he said. "And, therefore, as you heard tonight, his solution to virtually every problem we face is for Washington to tax more, borrow more and spend more.
"And the idea that more taxes and more government spending is the best way to help hardworking middle class taxpayers," Rubio said. "That's an old idea that's failed every time it's been tried."
Bigger government won't help people get ahead or create opportunities or inspire private-sector jobs, Rubio said.
And many government programs that claim to help the middle class end up hurting them instead, he said.
"Now does this mean there's no role for government? Of course not," Rubio said. "It plays a crucial part in keeping us safe, enforcing rules, and providing some security against the risks of modern life.
"But government's role is wisely limited by the Constitution," he said. "And it can't play its essential role when it ignores those limits."
Rubio addressed areas in which Republicans believe government should act, such as energy policy.
While saying solar and wind energy should be a part of the country's energy portfolio, Rubio said, "[Let's] open up more federal lands for safe and responsible exploration."
He called for student aid that doesn't discriminate against programs, such as online study, used by non-traditional students.
Rubio called for a plan to reduce gun violence but said, "Unconstitutionally undermining the Second Amendment rights of law-abiding Americans is not the way to do it."
He also defended the Republican plan to partially privatize Medicare, saying his party has offered "a detailed and credible plan" that will help Medicare and won't hurt today's retirees.
"Instead of playing politics with Medicare, when is the president going to offer his plan to save it?" Rubio asked. "Tonight would have been a good time for him to do it."
Rubio agreed with Obama on the need to simplify the tax code and reform the nation's immigration system.
"We can also help our economy grow if we have a legal immigration system that allows us to attract and assimilate the world's best and brightest," said Rubio, a member of a bipartisan group of senators working on an immigration reform framework. "We need a responsible, permanent solution to the problem of those who are here illegally. But first, we must follow through on the broken promises of the past to secure our borders and enforce our laws."
Despite differences, "I know that both Republicans and Democrats love America," Rubio said. "I pray we can come together to solve our problems, because the choices before us could not be more important.
"If we can get our economy healthy again, our children will be the most prosperous Americans ever," he said. "And if we do not, we will forever be known as the generation responsible for America's decline."