The Australian actor, who recently left his role as policeman Mark Brennan in the soap, reportedly got to know Celebrity Apprentice contestant and former Miss Universe Australia star Campbell when they met at the Melbourne Cup races last year.
According to the Herald Sun, the pair have been keeping in touch over Skype while McGregor tries to launch his acting career in Hollywood.
After taking part in last year's Celebrity Apprentice, Campbell was rumoured to be dating fellow contestant and model Didier Cohen. She has also been romantically linked to rugby player Danny Cipriani.
McGregor split from long-term girlfriend Chelsea Butler last year. In August, police were called to Butler's St Kilda home after an argument between the pair reportedly got out of hand. There was not thought to be any physical violence involved.
The most recent series of Celebrity Apprentice recently started filming in Sydney and Campbell has predicted that Charlotte Dawson or Ian Dickson will win.
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