PHILIP ELLIOTT, Associated Press

WASHINGTON (AP) — It's another clear sign that the White House is on Marco Rubio's mind.

The first-term Florida senator is getting together again with the conservative billionaire and politically active Koch (kohk) brothers.

The setting is a California gathering late Sunday that's organized by Freedom Partners. That's the hub for the political machine backed by wealthy industrialists Charles and David Koch.

Among the other possible 2016 Republican candidates expecting to attend are Texas Sen. Ted Cruz, Kentucky Sen. Rand Paul and Wisconsin Gov. Scott Walker.

Rubio's trip West is another sign he's seriously thinking about getting into the 2016 race.

He met with his core group of 300 supporters on Friday and Saturday on Miami's South Beach.

And he's ditching his Senate schedule this week to raise money for a potential campaign.

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