The problem with the U.S. labor market isn't only income inequality, it's also opportunity inequality—workers stuck in lower-paying jobs without the ability to get better positions, Sen. Marco Rubio, a possible 2016 GOP presidential candidate, told CNBC on Thursday.

"Our current safety net programs ... help alleviate the pain of poverty, but they do absolutely nothing to help people emerge from that poverty," Rubio said in a "Squawk Box" interview.

As Wall Street focuses on what Friday's employment report might reveal about the job market, Rubio seized on the 50th anniversary of President Lyndon B. Johnson's "War on Poverty" speech. On Wednesday, the Florida Republican stood in the room of the U.S. Capitol named after Johnson, criticizing big-government solutions that Democrats have been pushing for decades.

"Of course the cashier at a fast food restaurant makes less than the CEO of the company, that's not the issue," he said on CNBC. "The issue is whether that person ... gets stuck there forever or for a long period time without the ability to move up."



Rubio offered conservative solutions, such as shifting responsibility for many federal benefit programs to the states and providing a new form of federal "wage enhancement" aid to low-income wage-earners—designed to ensure that they make more money working than they might from receiving unemployment benefits. "We have to address the structural causes of that lack of opportunity. And they are social, they are educational, they are economic."

He specifically brought up the role stable families plays: "One of the greatest eradicators of poverty, one of the greatest factors in poverty ... is marriage," he said. "When a kid is being raised in a married family their likelihood of being in poverty drops dramatically."

Asked if that same dynamic could happen in children raised by same-sex couples, the senator replied: "We don't have any empirical evidence. That's a new dynamic emerging in the country." He said the issue of same-sex marriage should be addressed at the state level, as many states are already doing.

Rubio also declined to comment on the scandal enveloping Gov. Chris Christie, the New Jersey Republican who is also a possible 2016 candidate for president.

