Republican California gubernatorial candidate and billionaire Meg Whitman has now spent more than $100 million of her own money in an effort to become the Golden State's next governor.

The former CEO of eBay has written her campaign another massive check, this time to the tune of $13 million. The donation was filed Friday with the California secretary of state's office and brings Whitman's personal contribution to $104 million.

The lion's share of that money has gone to running television ads in the expensive California media market.

The investment has paid off, as Whitman now finds herself in a neck and neck race with her democratic opponent, the current attorney general and former Governor Jerry Brown.

The Brown campaign on the other hand has spent less than a million dollars to date and accuses Whitman of trying to buy the election. "Meg Whitman continues to pour unprecedented millions into a campaign of unprecedented dishonesty," said Brown spokesman Sterling Clifford. "Her ads have been proven false, her trickle-down tax breaks for the super rich are a proven failure, and the late night disclosure is all about keeping voters in the dark."

Brown's camp has $23 million in the bank and has yet to start airing television ads, preferring to hold onto the money for the all-important final push this fall.

However, Brown has been benefitted by television ads courtesy of independent expenditures from unions, the very reason Whitman's camp says she needs to keep writing checks.

"Meg is investing the necessary resources to fight the already $13 million in attacks Jerry Brown Inc. has launched to defend the status quo in Sacramento," said Whitman spokesperson Sarah Pompei. "She will continue discussing her plans to create jobs with Californians across the state."

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Jake Gibson is a producer working at the Fox News Washington bureau who covers politics, law enforcement and intelligence issues.