Anti-gay Republican Rand Paul will face a challenge for his Senate seat – from an openly gay Democrat.

Paul is currently trailing in his bid to secure the Republican Presidential nomination, well behind front-runners Donald Trump and Ted Cruz.

The Senator has increasingly rallied against LGBT rights, insisting employers should be able to fire people for being gay because gays should keep their “lifestyle… in their house”.

He also claimed that he is ‘offended’ by the concept of same-sex marriage, insisting it “offends myself and a lot of people.

Of gay rights, he claimed: “I don’t think I’ve ever used the words gay rights because I don’t believe in rights based on your behaviour.”

However, influential Lexington Mayor Jim Gray has declared his intention to run to unseat the Kentucky Senator, planning to run for his Senate seat as a Democrat.

Gray told the Lexington Herald-Leader: “I feel like that there’s an environment in Washington that’s toxic, and people across the country, and including Kentucky, are looking for alternatives.

“I certainly think that he’s been spending more time focused on his presidential campaign than he has in the interests of Kentucky, and because of that he’s vulnerable.”

Gray said he does not believe voters will focus on his sexual orientation – adding: “I know what it’s like to challenge conventional thinking and conventional patterns.

“What I believe people want is performance and results. That’s what they are about. That’s what counts.”

Elections for the United States Senate will be held on November 8, 2016.