Senator Marco Rubio last week sent out a long fundraising letter laying out the issues he was fighting for. There was one major omission: The big immigration bill that he and seven other senators of both parties have crafted and that may pass the Senate this year.

In the almost 2,000-word solicitation from the "Rubio Victory Committee," the freshman Florida Republican presents an ambitious agenda: "To stop the growth of government, encourage job creators to do what they do best, keep tax rates low, repeal government programs such as Obamacare, and protect the freedom and liberty of all Americans."

He makes only a passing reference to his parents "coming to America in 1956," and doesn't mention the hot-button topic of immigration reform or the legislation he is sponsoring.

Rubio, a conservative favorite to be the next Republican presidential candidate, has been credited with doing an effective job of defusing right-wing opposition to the immigration proposal. He has been especially active in dealing with conservative talk-radio and blogs. He has had mixed success convincing conservative Republicans in the Senate to support the bill.

Rubio's supporters say that if an immigration bill is passed, it will become a signature piece of legislation for the young lawmaker. But the junior senator from Florida still has a lot of work to do.

(Albert R. Hunt is a Bloomberg View columnist. Follow him on Twitter.)

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