A sex scandal involving a rising star in the Republican party is a man who co-chaired Mitt Romney's campaign in Arizona.

He's a no-nonsense, tough-on-immigration sheriff... now dealing with allegations that he threatened to deport his secret ex-lover, a Mexican man.

ABC's David Kerley has the details.

This hard-charging, rising star in the Republican party has battled the Obama administration with his tough stance on immigration.

Sheriff Paul Babeu of Pinal County said, "It's time we stand up for America and our rights.  It's time that we put America first."

Is now caught in a sex scandal involving a Mexican male the sheriff running for congress co-chairman of Mitt Romney's Arizona campaign.

Until pictures were printed in a newspaper, with allegations that the sheriff allegedly threatened to deport this Mexican man if he revealed
their sexual relationship.

Babeu said, "I'm here to say all these allegations that were in one of these newspapers are absolutely, completely, false."

Then in this extraordinary press conference, this admission...

Babeu said, "Except for the issues that refer to me as being gay.  Cause that's the truth.  I am gay."

That revelation sent shock waves not just through the sheriff's county, but also national politics.  Within hours of the allegations of a threat the sheriff resigned from his position with the Romney campaign.

With Romney celebrating the 10 anniversary of the Winter Olympics in Salt Lake City, his campaign released a statement within minutes:

"Sheriff Babeu has stepped down from his volunteer position with the campaign so he can focus on the allegations against him.  We support his decision."

The Sheriff doesn't not deny a relationship with the Mexican man who worked on his campaign, but he plans to fight the other charges.

Babeu said, "And a lot of people have reached out to me already friends and voters, supporters and said sheriff, this changes nothing. that who you are I know you personally, I know your performance and I value and appreciate who you are."

Not only will he fight the allegations, the sheriff says he will continue his campaign for congress.