And he has stated that one of his main focuses will be on the River Murray.

"Replacing one Liberal with another doesn't help the cause at all (to save the River Murray)," Mr Day said.

As reported in last week's edition of The Times Mr Day (56) resigned from the Liberal Party, stating that he was unhappy with the preselection process and a result that he believed was "engineered".

He said he was taken by surprise to be approached by Family First to run as their candidate but says the party is one of common sense and that he had been watching them closely.

Mr Day is the Managing Director of Home Australia Pty Ltd, which turns over in excess of $300 million annually and owns (amongst others) the Homestead Homes brand in South Australia.

He was awarded the Order of Australia in 2003 for services to the housing industry and social welfare.

Mr Day stood as the Liberal candidate in the seat of Makin in last year's Federal election and lost to Tony Zappia.

Mr Day lives in Houghton, which is just outside of the Mayo electorate.

His 2007 campaign in Makin attracted a lot of media attention, with speculation that he had spent in excess of $100 000 of his own money.

In Mayo he sees the big issue as the state of the river, the lakes and the Coorong.

"Together with Nick Xenophon, Family First holds the balance of power in the senate," he told The Times.

"Electing a lower house Family First member in Mayo gives tremendous clout towards securing the river".

He said other issues of importance are the roads, Internet coverage, giving help to pensioners, families and farmers.

Transport is also a key issue with Mr Day believing the Victor Harbor - Adelaide Road needs to be improved.

He is also supportive of Family First's policy for train services to regional areas.

He also sees small business owners as very important in the electorate in securing employment opportunities.

"Big business are investing in technology to reduce their workforce," he said.

"Small business are the great potential for employment growth".

Mr Day attended the public meeting addressed by Karlene Maywald in Goolwa on Monday and will also be at the vigil for the River Murray on Sunday.