Florida Republican Sen. Marco Rubio’s latest fundraising letter completely ignores his signature issue: his work with Democrats to rewrite the nation’s immigration laws and add 46 million immigrants by 2033.

“Now, with the full weight of the liberal Washington elite’s attack machine firmly fixed on me in a frantic attempt to diminish my effectiveness… I’m reaching out to ask you to lend me a hand today,” says the letter, which is signed “Proud to Stand, Marco Rubio.”

In fact, Rubio has gotten a great deal of supportive media coverage from liberal elites, who have repeatedly touted him as a possible 2016 presidential candidate because of his efforts to pass the immigration bill, which is unpopular among GOP base voters.

In February, Time magazine gave him its front cover to tout the Senate’s emerging immigration deal, which is backed by Washington’s progressive, lobbying and business elite, with the headline, “The Republican Savior.”

He’s also getting support from business elites, who are funding ads that applaud his work on the immigration bill. The bill would double the inflow of low-wage workers and customers.

After the Senate voted through the immigration bill that he had championed to conservative media outlets, leading Democrat senators lauded his work. Rubio’s task was to “work over the conservative universe, particularly the conservative opinion-maker universe… [and] neutralize them,” New Jersey Sen. Bob Menendez, one of the four Democratic Senators who helped draft the Gang of Eight’s bill, The New Yorker reports.

Rubio “is the real deal. He is smart; he is substantive. He knows when to compromise and when to hold. And he’s personable,” said New York Democrat Sen. Chuck Schumer, who led the effort to pass the bill through the Senate.

Rubio also won plaudits from South Carolina Republican Sen. Lindsay Graham, the leading GOP supporter of the immigration bill. “Marco Rubio has been a game changer in my party… Marco has been indispensable,” he told NBC News on April 7.

But Rubio has been hammered by former Alaskan Gov. Sarah Palin.

“It’s beyond disingenuous for anyone to claim that a vote for this bill is a vote for security… This bill isn’t about fixing problems; it’s about amnesty at all costs,” Palin wrote in a Facebook post in late June.

Rubio has been distancing himself from his liberal allies since the Senate approved the bill.

On June 26, one day before the final vote, he began mending fences with his conservative supporters.

Conservatives and tea Party members “are increasingly unhappy about the immigration reform proposal in the Senate… [but] in my heart and in my mind, I know that we must solve this problem once and for all, or it will only get worse. It will only get harder to solve,” he said in a floor speech.

Immediately after the vote, he avoided the media scrum outside the Senate’s doors, leaving Sens. Graham and McCain to declare victory to an audience of mostly supportive reporters.

Without mentioning immigration, Rubio used his fund-raising letter, which included a plain “Rubio Victory” bumper sticker, to tout his work on a series of proposals backed by conservatives in his home state and nationally.

“No matter how many person political hits I take, I will never back down when it comes to improving our economy, curbing the federal debt, lowering tax rates or preserving the American dream for the next generation as my my parents did for me,” the letter reads.

The letter also mentioned Rubio’s standing in his home state of Florida.

“Make no mistake, the liberal forces attacking me in Florida will not rest in their quest to damage every shred of my credibility,” the pitch continues.

His letter suggested that his fund-raising was declining. “My friend, you and I must not allow the New York and Washington liberal elite to outspend or outwork us in this fight… That’s why just a few weeks ago I asked my most loyal supporters to help us beat an anticipated dip in fundraising.”

Rubio’s polls took a hit over the last few months as he ramped up his support for the immigration overhaul.

“In the four national surveys conducted in January, an average of 20 percent of Republicans said they would support Mr. Rubio for the party’s [presidential] nomination in 2016,” The New York Times reports. “That number dropped to an average of 11 percent in the four primary polls conducted in June.”

Rubio’s slide in the polls reduces the chance he’ll try to beat out out Republicans — such as his mentor, Florida Gov. Jeb Bush — for the 2016 nomination.

In home-state polls, Rubio has lost GOP support while gaining some support from swing-voters.

In 2009 and 2010 Rubio positioned himself as an opponent of amnesty.

“I am strongly against amnesty,” he said in 2009. “The most important thing we need to do is enforce our existing laws… I am not, and I will never support any effort to grant blanket legalization/amnesty to folks who have entered, stayed in this country illegally.”

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