The Liberals have claimed victory in a key Victorian byelection seen as a preview of what to expect when the rest of the state hits the polls in November .

As counting continued in the Mornington peninsula seat of Nepean, the Liberal candidate, Anthony Marsh, appeared to be in a commanding position in a significant boost to opposition leader Jess Wilson.

With close to 80% of the vote counted, Marsh had 38.5% of the primary vote, and 63.4% on a two-candidate basis.

However, the Victorian Electoral Commission was initially running the two-candidate vote as a race between the Liberals and independent Tracee Hutchison.

Hutchison was in second place early in the count, but later slipped behind One Nation’s Darren Hercus.

Hercus had 24.7% of the primary vote to Hutchison’s 21.3%.

In a speech to supporters, Marsh said he was “so glad I could bring it home for you tonight.…