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Florida Republican Sen. Marco Rubio on Sunday defended his plan to develop a scaled-back version of the DREAM Act, arguing that his proposal represents not amnesty, but an effort to tackle the “humanitarian issue” of undocumented immigrants who were brought to the country as children.

Sen. Marco Rubio (R-Fla.). (AFP PHOTO/Jewel Samad/AFP/GettyImages)

Former Massachusetts governor Mitt Romney, the presumptive GOP presidential nominee, has yet to state a position on Rubio’s plan, and Rubio said Sunday that he did not expect Romney to weigh in on the proposal because it has yet to be finalized.

Rubio’s remarks represent a move by the GOP rising star to reach out to Hispanic voters, a key constituency this fall. Polls show Romney trailing President Obama by two-to-one among Hispanic voters, and some Republicans believe that Rubio – who is Cuban American – could give the GOP ticket a lift among Hispanic voters if he were to be chosen as Romney’s running mate.

Asked by host Chris Wallace about Romney’s poor polling numbers among Hispanics, Rubio argued that “there’s no such thing as the Hispanic vote” and noted that one of his cousins is the Democratic state Senate leader in Nevada.

He also argued that Romney won’t lose Hispanics by two-to-one in the state of Florida.

“I think he has the opportunity to win Hispanics in Florida,” Rubio said.

In the wide-ranging interview, one of his first as a top surrogate for Romney, Rubio also delivered sharp criticism of Obama, who formally kicked off his reelection campaign Saturday with events in Ohio and Virginia.

Rubio cast Obama as a president who campaigned four years ago as someone who would bring the country together but who instead has resorted to tactics of political division.

“He was going to be a post-partisan uniter to bring Americans together, and three- and-a-half years later, the president has become just like anybody else in Washington, D.C.,” Rubio said. “And in his obsessive effort to win his reelection, he has lost himself and he has lost what makes him different.”

Last week’s visit by Obama to Afghanistan to mark the anniversary of the death of Osama bin Laden – and the campaign’s release of a Web video questioning whether Romney would have authorized the raid that killed him— represents “one example about how his administration has become just like everybody else,” Rubio argued.

He said that while Obama “made an important and wise decision” in authorizing the raid that killed bin Laden, “he has taken something that should unite the American people, a moment for pride for out country, and instead turned it into a weapon for political warfare.”

Rubio had criticism not just for Obama but also for Vice President Joe Biden, whose record on foreign policy, the Florida senator contended, “is one of being wrong on everything that he’s ever advised or everything he’s ever asked for -- from dividing Iraq, to admittedly telling the president not to go in and do this operation.”

“That being said, I also think he is a very nice person but Vice President Biden has the tendency to say some interesting things to say the least,” Rubio added.

On the issue of Chinese dissident Chen Guangcheng, Rubio sided with Romney, who last week criticized the Obama administration’s handling of the matter.

“There’s this propensity that this administration seems to have of an unwillingness to forcefully assert America’s values,” Rubio said. “We’ve seen that in a number of occasions. Tragically, we saw that in 2009 during the green revolution in Iran. And we see that again here now, in China, where somehow this administration looked almost reluctant to forcefully assert the United States. . . respect for human rights, democracy, freedom, et cetera.”

He said that the episode highlighted that “what we know for a fact we are dealing with now (in China) are people that are paranoid and are control freaks and a totalitarian system.”

Obama senior adviser David Axelrod defended the president in a separate interview on ABC’s “This Week.”

“(Obama) ordered a mission that was — was, frankly, risky, dangerous,” Axelrod said of the bin Laden mission. “Gates said it was one of the most courageous, one of the gutsiest decisions he’s ever seen a president make. And it turned out successfully. . . . If it hadn’t, you’d better believe the other side would be talking about it, and Mitt Romney would be the first one.”

Asked about Romney’s criticism of the Obama administration on Chen, Axelrod charged that the GOP frontrunner is “blunderbussing” based on incomplete information.

“What’s shameful is when presidential candidates are so craven to score political points that they speak irresponsibly on half information at a time when the president is trying -- and the administration is trying — to resolve a situation that is very, very sensitive and very difficult,” Axelrod said.