Lt. Gov. David Dewhurst's former adviser Kenneth "Buddy" Barfield pleaded guilty on Tuesday to charges of wire fraud, making a false tax return and embezzlement of funds contributed to a federal candidate.

Barfield's plea agreement, which was submitted in federal court to U.S. Magistrate Judge Mark Lane, stated that he took $1.8 million from the David Dewhurst Committee and the Dewhurst for Texas campaign funds from 2008 to 2012.

Barfield had been one of Dewhurst's most trusted advisers prior to 2012, when an accountant discovered that significant amounts of money were missing from Dewhurst's campaign accounts.

After being confronted about the discrepancies, Barfield left the campaign and promised to repay the money. He has since had to sign over his spacious Austin house as part of a settlement agreement in a civil lawsuit.

The revelation also prompted investigations that ultimately resulted in charges being brought against Barfield by federal authorities.

In his plea, Barfield acknowledged submitting inaccurate invoices to campaign accountants, prompting them to transfer money to accounts that were under his name or the names of his consulting company. He would then withdraw the funds and, in some cases, use them for personal purposes, such as the mortgage on his home or the tuition for his kids' school.

At his sentencing hearing, which has yet to be scheduled, Barfield could face a total of up to 28 years in prison and more than $600,000 in fines and fees, along with restitution and supervised custody following prison time. In return for his guilty plea, prosecutors are recommending sentencing on the low end of the punishment spectrum. Lake said that since the crimes were federal, Barfield would not have the option of parole if sentenced to prison time.

For the wire fraud charge, he could face up to 20 years in prison, a $250,000 fine and restitution. For filing a 2008 tax return claiming he had no taxable income, he could face up to three years in prison and a $100,000 fine. He also faces up to five years imprisonment and $250,000 in fees along with restitution for the charge of embezzling money from Dewhurst's U.S. Senate campaign.

The scandal surrounding Barfield, who had been a familiar face and trusted figure in Texas Republican circles for years, caught many by surprise. He previously worked on Clayton Williams' unsuccessful gubernatorial campaign in 1990. He also worked on political issues for the Koch brothers in the 1990s before going to work for Dewhurst.