One of Pauline Hanson's former senators has been referred to police over his nomination to contest the coming federal election after the Australian Electoral Commission questioned his declaration that he was fit to stand for Parliament again.

The commission referred Rod Culleton, a former Western Australian senator for Pauline Hanson's One Nation, to the police on Wednesday over concerns at his prior disqualification because he was an undischarged bankrupt.

The decision came after the commission finalised the list of candidates for the election and their positions on ballot papers, in a random draw that has helped One Nation and another anti-immigrant party, Rise Up Australia.

The Liberal Party has also gained an advantage in the contest for the Senate after the random draw gave it prime position on the Victorian ballot paper, as well as a higher position than Labor in NSW.