National Party candidate David O'Brien was officially declared as Western Victoria's fifth representative in the upper house by the Victorian Electoral Commission yesterday.

The Coalition gained four Labor seats after counting for the Legislative Council was finalised, giving the Liberal and National parties a majority of 21 in the 40-seat house.

Labor finished with 16 seats and The Greens retained three, with the Democratic Labor Party (DLP) losing its solitary seat to Mr O'Brien.

The complex nature of preferential voting in the Legislative Council meant the final result for several fifth-place seats was not known for more than a fortnight after the November 27 state election.

Liberal MP David Koch along with Labor MPs Gayle Tierney and Jaala Pulford were re-elected to represent the region at the poll.

Former Victorian Farmers Federation president Simon Ramsay was also elected as a new Liberal MP for Western Victoria, effectively replacing retiring MP John Vogels.

Premier Ted Baillieu said the Coalition would treat the parliament with respect.

He also maintained that the Legislative Council would remain as a "house of review" despite the Coalition majority.

"We will deal with the Parliament as we have always dealt with the Parliament, and that is with respect and in opposition we did that too," the new Premier said.

Opposition Leader Daniel Andrews congratulated the Coalition on achieving a majority in both houses but said the government now had no excuse for not delivering on its election promises.

"We intend to hold the government accountable, we intend to make sure that there's no back sliding, there's no weaseling out of the promises that have been made," he said.

with AAP