It’s been a bitter battle for the Republican nomination to fill Kay Bailey Hutchison’s U.S. Senate seat, and three weeks out from runoff election day, the candidates aren’t letting up on their attacks.

Ted Cruz’s campaign is confirming claims it missed a filing deadline for Cruz’s financial disclosure forms. They acknowledged the mistake and that they were forced to pay a $200 fine for filing two months late.

The Dewhurst campaign was quick to jump on the story, calling him "Short Fuse Cruz."

"Today it was exposed that Ted Cruz failed to file his personal financial disclosure with the Senate Ethics Committee and was penalized with the maximum fine," said Dewhurst for Texas Advisor Mark Miner in a statement. "What is Short Fuse Cruz hiding? What other shady clients is he trying to shield? The Dewhurst for Texas campaign demands that Ted Cruz release his Personal Financial Disclosure form, and disclose other possible fines and campaign ethics breaches. We seriously doubt this is the only one."

The Cruz campaign fired back, challenging Lt. Gov. David Dewhurst to explain why his office deleted past speeches from his official web site. The Cruz campaign’s Twitter account tweeted "[David Dewhurst] Speech Advocating Guest Worker Program for Illegal Immigrants Vanishes from Site," linking to a story on the National Review’s website.

Dewhurst’s campaign says it was the Lieutenant Governor’s office which asked for all past speeches to be removed. A spokeswoman for Dewhurst said they do not know why the state office wanted the speeches taken down.

The Associated Press contributed to this report.