What single kingdom does Christ set up on earth when He returns?

Les teaches that all through Scripture there is only one kingdom, and it is the kingdom Christ will set up on earth when He returns to become King of kings and Lord of lords. This kingdom of heaven is going to be the kingdom on earth; it is the same kingdom. It is not a spiritual, ethereal, invisible kingdom only, although spiritual matters are involved, because this kingdom is spiritual, physical, political, and it will come to its fruition when Christ returns and sets it up on the earth. Jesus is the essence of the kingdom, and John the Baptist announced that the kingdom of heaven was at hand because Jesus was just around the corner. Les also explains that to become part of that literal, physical, political kingdom, there must be an inner spiritual relationship with God, as when Jesus told Nicodemus that except a man be born again he cannot see the kingdom of heaven.