Murray appears to claim that the killing has been covered up because the US Defense Department is part of the plot, and is using his DNA.
He asks that all the votes that were received by Lucas should be given instead to Murray.
The aspirant congressman has committed not to use such a body double at any time.
"I will NEVER use Artificial Intelligence look alike to voice what The Representative's Office is doing nor own a robot look alike," Murray says on his website. (Much of the rest of Murray's policies are in line with Republican party policy, including opposing tighter restrictions on gun ownership and a reduction in the state's role in citizen's lives.)
Lucas has rejected the claims. Speaking to a local TV news station, he said that he was not a robot and has never been to Ukraine.
"It does come as kind of a shock to read that you're not you," he said. "Many things have been said about me, said to me during course of my campaigns. This is the first time I've ever been accused of being a body double or a robot."
Lucas said that he faced Murray in an election two years ago, where he stood as a Democrat.
Watch: New Japanese robot can read emotions
- UK Independent