Labor and the Greens will battle out the Batman by-election without a Liberal candidate.
Victorian Liberals president Michael Kroger says his party won't stand a candidate in the Batman by-election, boosting the Greens' chances of winning the seat from Labor.
The by-election is being held on March 17 to replace Labor's David Feeney, who quit over his dual citizenship.
"We are not a vote-channelling machine for Mr Shorten," Mr Kroger told Sky News on Friday.
Mr Feeney won the seat in 2016 in a tight contest with the Greens, on the back of Liberal preferences.
Mr Kroger acknowledged the decision would improve the chances of the Greens winning the seat.
"It will certainly make it more likely the Greens will be the favourite to win," he said.
The ALP has endorsed former ACTU president Ged Kearney as its candidate.