Rubio close to locking up Adelson's support: Report

Marco Rubio may soon get a boost from one of the Republican Party's key donors.

Billionaire casino magnate Sheldon Adelson is leaning toward supporting the Florida senator for the Republican presidential nomination, Politico reported Monday, citing sources. Adelson could endorse Rubio as early as the end of the month, the report said.

Adelson, the deep-pocketed Las Vegas Sands chairman and CEO, would provide a vital cash stream to Rubio's campaign. The 82-year-old funneled more than $90 million into conservative Super PACs in the 2012 election cycle, according to the Center for Responsive Politics.

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Sheldon Adelson

Adelson praised the 44-year-old Republican contender when they met in Las Vegas last week, Politico said. He is among a group of uncommitted megadonors candidates continue to court.

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Rubio currently sits third in the race, according to an aggregate of national polls compiled by RealClearPolitics. However, his fundraising lags well behind former Florida Gov. Jeb Bush and Texas Sen. Ted Cruz.

Rubio's campaign and Las Vegas Sands did not immediately respond to CNBC's request to comment.

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Read the full story from Politico here.