Florida Republican Sen. Marco Rubio’s top lawyer in the closed-door effort to draft a new immigration bill is a Democratic donor who earns his living by bringing foreign workers into the country on behalf of corporations and universities.

The lawyer, Enrique Gonzalez, is a partner at the nation’s largest immigration firm, whose future depends on the outcome of Gonzalez’s closed-door work.

Rubio hired Gonzalez in January, when he was a partner at the Coral Gables, Fla., office of Fragomen, Del Rey, Bernsen & Loewy.

Gonzales’ LinkedIn profile describes his “skills & expertise” as “immigration law, H-1B, naturalization, citizenship appeals … [and] international law visas.”

Fragomen’s website says the firm has “a diverse client base ranging from individuals and small businesses to Fortune 500 companies … [plus clients in] Colleges, Universities and Research Institutions, as well as in the energy, entertainment, hospitality (including cruise lines), health care and technology industries.”

“We assist companies with all types of business immigration services, including a particular focus on corporate compliance issues (I-9 and E-verify), J-1 Exchange Visitor programs and H-2B visa issues [and] our vibrant individual practice encompasses investors (including EB-5), artists, entertainers and athletes, as well as a broad range of family immigration matters,” the firm said.

Gonzalez cut his ties to the firm when he left in January, R. Blake Chisam, a D.C.-based Fragomen partner, told TheDC. “It was a clean break,” he said.

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From 2008 to 2012, Gonzalez also donated $6,950 to Democratic Rep. Joe Garcia, who ousted Republican Rep. David Rivera from his Florida seat in 2012.

In January, Garcia applauded Rubio’s decision to join the “gang of eight” senators’ comprehensive immigration plan.

“I wholeheartedly welcome Senator Rubio’s and others evolution on this important issue, and welcome with them with open arms to join our cause. … What is most encouraging about their plan is the earned pathway to citizenship, which must be reasonable and begin quickly,” he said in a statement.

Gonzalez did not contribute to any GOP candidates, according to the Open Secrets website.

A March 20 report by the Washington Post said Rubio’s pending bill would double the number of H-1b visas that companies use to hire low-cost high-tech workers, and allow universities to provide residency cards and work permits to an unlimited number of fee-paying graduate foreign students.

Critics say both measures would reduce wages and employment prospects for American middle-class college graduates.

Gonzalez is also a speaker at conferences organized by the American Immigration Lawyers Association, which is a special-interest network for the nation’s immigration lawyers.

Rubio’s office did not respond to questions from The Daily Caller. However, in recent weeks he has said that he wants to protect U.S. workers, and has positioned himself for the 2016 presidential race as a champion of the middle class amid a rapidly changing, high-tech, global economy.

The immigration bill is being drafted by eight senators and their expert staffers, and is expected to be released after the Easter recess.

Sens. Chuck Schumer and Lindsey Graham, the chief drivers of immigration reform in their respective parties, each favor passage of a comprehensive bill that provides work permits and citizenship to at least 11 million illegal immigrants, and eventually to their foreign family members. They also want the bill to allow companies to bring in more foreign workers for tough agricultural jobs, low-status service jobs in hotels and restaurants, and high-status, high-skilled professional jobs.

Under current law, companies can bring in roughly 200,000 workers each year — or approximately one foreign worker for every six Americans who graduate from school or college.

The proposed law reportedly would add 60,000 to 85,000 H-1B visas, and an unlimited number of green cards for university post-grads.

Schumer’s top immigration aide is also an immigration lawyer, whose career will be shaped by the law he is helping to write. Leon Fresco previously worked at Holland & Knight, where he “represented corporations in … corporate immigration matters,” according to EB5info.com, a website on immigration law.

Rubio joined the senators’ group after he dropped his own calls for the passage of several small-scale immigration reforms, and abandoned his demand for a so-called “trigger” that would freeze the awarding of visas and green cards until enforcement measures were actually implemented.

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