Benjamin Sparks was accused by the 46-year-old woman of giving her a five-page 'slave contract' that required her to be nude at all times, have sex on demand and wear a collar in private. He is pictured in an undated image

A Las Vegas political adviser who worked on Mitt Romney's 2012 presidential campaign is facing claims from his ex-fiancee that he sexually enslaved and beat her.

Benjamin Sparks was accused by the 46-year-old woman of giving her a five-page 'slave contract' that required her to be nude at all times, have sex on demand and wear a collar in private.

The unnamed woman claimed Sparks, 35, 'did not take no for an answer' and recently 'back-handed me... and forced himself on me'.

She presented a series of documents, texts and emails as evidence of the slave contract to the Review Journal. The contact was dated November 3, a day after they first met. Sparks has not responded to the Review Journal's requests for comment.

'He was very demanding and did not take no for an answer,' Sparks' ex-fiancée told the newspaper. 'Over the last month it escalated into very rough sex where he'd actually hurt me. He back-handed me … and forced himself on me.'

The alleged abuse continued until police responded to a domestic dispute at the woman's home on March 29, which officers said gave 'probably cause to arrest Sparks for domestic battery'. Sparks evaded police and is said to have fled to Texas.

Sparks worked for Mitt Romney as a spokesman or senior staffer in 2012, and served a similar role during the anti-recall campaign of Wisconsin Gov. Scott Walker in 2012, according to the Review Journal.

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Sparks worked for Mitt Romney (seen addressing the Utah County Republican Party on February 16) as a spokesman or senior staffer in 2012, and served a similar role during the anti-recall campaign of Wisconsin Gov. Scott Walker in 2012

He was fired from his most recent job - helping Republican Cresent Hardy regain her 4th Congressional District seat - after the March 29 incident.

He was also working with Republican Yvette Herrell on her campaign for the 2nd Congressional District of New Mexico. Herrell refused to tell the Review Journal if a decision had been made about his future.

Sparks was a consultant for Red Rock Strategies, a political consulting company that claims to have helped more than two dozen people win seats in the U.S. Congress.

His ex-fiancee said the March 29 incident stemmed from a disagreement she had with Sparks after he allegedly asked her to have sex with other women in front of him while wearing a blindfold.

A police report says the couple met in a parking lot to discuss their falling out, before returning home in different vehicles.

Officers said the woman tried to leave after suspecting Sparks was under the influence of drugs and drink but he did not let her.

Sparks was also a senior staffer on the anti-recall campaign of Wisconsin Gov. Scott Walker in 2012. Walker is pictured left on February 14 speaking to reporters in Madison

Instead, Sparks phoned 911 claiming the woman had attacked him and tried to commit suicide. Police arrived at the Las Vegas address to find Sparks gone and the woman with a lost fingernail and a bruised thumb.

Sparks appears to have deleted his Twitter page.

Meanwhile, an August 29, 2017, media release announcing his appointment to Red Rock no longer appears on the company website.

The website claims Red Rock helps electoral candidates by combining 'veteran political strategists' with people who have knowledge of social media campaigning.

It also serves corporate clients, including victim's rights advocacy organisations, although it is unclear if Sparks carried out any of this work.

The firm's website carries testimonials from political figures including Crescent Hardy, New Mexico Lieutenant Governor John Sanchez and former California Senator Jim Brulte.

DailyMail.com has contacted Red Rock for comment.

