Labor's Herbert win means Turnbull has a majority of only one

Labor has won the Queensland seat of Herbert, but the Liberal National Party has left the way open for a court challenge.

The Australian Electoral Commission declared on Sunday that ALP candidate Cathy O'Toole had beaten sitting Liberal Ewen Jones by 37 votes, after a recount.

The Queensland LNP said in a statement it was “examining a number of issues reported to the party to determine if all Herbert electors were given the opportunity to vote”. It will then decide whether to appeal to the Court of Disputed Returns, which is the High Court, calling for a fresh election in the seat.

There have been suggestions that some soldiers missed out on voting because they were away on exercises, and that there was a problem with hospital patients not having the opportunity to cast a vote.

Herbert is the last House of Representatives seat to be finalised. The result means the Turnbull government has the narrowest possible majority – 76 seats in the 150-member house.

A new election held in Herbert would give Malcolm Turnbull the chance, if the Liberals could reverse this result, to increase the government’s house numbers beyond the bare margin of one. But it could also sour the start of this term for Turnbull if a second vote confirmed Labor in the seat.

Special Minister of State Scott Ryan said there would be about 40 days for a challenge to be lodged, from the return of the writ in a week’s time.

The Senate count will be finalised this week.