Mr Corboy won't be joining Mr Jasper in Rutherglen when the former state parliamentarian is expected to reaffirm his support for the National Party candidate in the July 2 election.

But if, as expected, Mr Jasper recommends voters preference independent Cathy McGowan second and not the Coalition's other contender in Indi, Sophie Mirabella, lingering tensions between Liberals and Nationals will likely explode.

Mr Jasper's endorsement of Ms McGowan three years ago was viewed as a pivotal moment in the campaign which resulted in Mrs Mirabella losing Indi by only 439 votes.

The Coalition candidates equally require as many second preferences as they can muster to unseat Ms McGowan who holds the seat by only 0.3 per cent.

Mr Jasper told The Border Mail last month he would be supporting Mr Corboy in the battle which is expected to be decided on preferences again.

"I appreciate the years of service Ken has given as a member of parliament as well as his continued commitment to our community," Mr Corboy said.

"Ken has the right as an individual, like every other member of our community, to decide how he numbers his ballot paper in the upcoming election.

"It is what makes our voting system great.

"These discussions around preferences just take away from what I am really focused on, delivering what is best for our electorate."

He will spend the day campaigning at Barnawartha saleyards with Senator Bridget McKenzie and then the Albury pre-poll centre.