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Charlie Neibergall, File, Associated Press
In this July 17, 2015 file photo, Republican presidential candidate Wisconsin Gov. Scott Walker speaks in Cedar Rapids, Iowa. Walker and fellow candidate Carly Fiorina and Scott Walker are to speak at gathering hosted by the conservative political donors Charles and David Koch.

DANA POINT, Calif. — Former Florida Gov. Jeb Bush and four other GOP presidential candidates are at a luxury Southern California resort speaking to the billionaire Koch brothers and other conservative donors.

Industrialists Charles and David Koch have convened about 450 like-minded business leaders this weekend to listen to Bush, Florida Sen. Marco Rubio, Wisconsin Gov. Scott Walker, Texas Sen. Ted Cruz and former technology executive Carly Fiorina.

On Saturday, Charles Koch welcomed the donors and encouraged them to stop "crony capitalism," even if those policies hurt their bottom lines.

Although groups backed by the Kochs say they aren't endorsing anyone in the GOP primary, donors at the retreat have the ability to write million-dollar checks to boost a candidate's chances.

The event is private.

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