9:30pm: With 33.37 per cent of the vote counted the Liberals lead with 157,692 (33.2%), ahead of Labor 100,674 (21.2%), Greens 75,470 (15.9%), Palmer United Party 59,948 (12.6%) and the Nationals 18,404 (3.9%).
The Liberal Democrats are the best of the minor parties followed by the Australian Christians, Help end Marijuana Prohibition, Shooters and Fishers and Sex Party.
9:15pm: The Liberal, Labor and the Palmer United parties are set for a hard-fought three-way contest for the final two West Australian senate seats.
An hour after the polls closed on Saturday night, Liberal senators David Johnston and Michaelia Cash were tipped to win their seats, as were Labor's controversial candidate Joe Bullock and the Greens' Scott Ludlam.
With early indications of a 15 per cent drop in voter turnout, Labor's Louise Pratt, the Liberals' Linda Reynolds and Palmer United Party's Dio Wang were considered the front-runners to claim the final two seats.
Voters may have to wait weeks before the final two seats are decided.
More details here.
8:30pm: The Liberal Party is battling to hold a third Senate seat in Western Australia in Saturday's historic byelection for the upper house as an advertising blitz from mining magnate Clive Palmer begins to bite.
Polls - albeit with a small sample size - are suggesting the Palmer United Party has doubled its vote to 10 per cent, enough with preferences to get a Senate position.
Read the full story here.
6:01pm: And the polls have closed in WA. That will be the end of our rolling coverage for now but click back to this story for updates on how the vote is progressing throughout the night.
5.45pm: There have been reports that a ballot box in Maida Vale has split open with the votes spilling out on to the floor and then placed in a plastic bag.
The Australian Electoral Commission has been alerted to the broken ballot box.
5:38pm: Less than half an hour to vote! Better get in quick if you haven't had your say yet.
5:27pm: VIDEO: Election watchers say there was no sign so far of the much feared "election fatigue" forecast for Saturday's Senate election in WA.
4.52pm Margaret River voters headed out to local schools today to cast their votes in the re-run Senate election.
Did you vote in Margaret River? Check out our special election gallery.
4.42pm Have you voted yet?
The Australian Electoral Commission advises that polls close at 6pm sharp tonight.
4.35pm Check out our gallery of photographs from all the voting action in Busselton today.
West Busselton and Vasse Primary Schools saw a big turnout of voters for the re-run election
4.23pm Mandurah voters were out in force to vote this morning.
Check out the Mandurah Mail's coverage here.
4.14pm Clive Palmer's advertising blitz might have just paid off, with the Liberal party battling to hold onto a third Senate seat.
Polls are suggesting that Palmer United may have doubled its vote to 10 per cent.
Palmer United's influence, alongside Ricky Muir from the Motoring Enthusiast Party, may be able to block Coalition legislation alongside Labor and the Greens.
4.00pm People in Bunbury were not happy about having to vote again.
Our reporter spoke with voters as they exited the polls.
Check out the gallery of photographs and their thoughts here.
3.25pm It turns out the much-feared election fatigue forecast was wrong after all.
Phil Diak from the electoral commission has said a quarter of a million West Australians had already voted before the polls opened this morning.
Read about how voter numbers appear to be up compared to the September election.
3.15pm West Australians are sharing their election Saturday with the people of Afghanistan. who are today voting in elections to mark the first democratic transfer of power since 2001.
while some West Australians are annoyed at bring inconvenienced by the election re-run, consider our how fortunate we are relative to the violence shrouding the Aghan elections.
3.02pm The man behind the success of many minor and micro parties over the last decade believes electoral laws will be changed before the next election.
See what "preference whisperer" Glenn Druery has to say here.
2.52pm Voters are heading to polling booths in local areas including Bridgetown, Donnybrook, Balingup and Kirup today to vote in the re-run Senate election.
The vote will determine six Senate seats, and could have a significant impact on the Abbott government's ability to pass legislation.
2.50pm Who will you be voting for today? Take our poll and let us know.
2.47pm What kind of voter are you?
Read James Taylor's column on the different kinds of voters heading to the polls today.
2.32pm There were more early votes cast in this election than in September 2013.
2.15pm Voters are reminded to get their votes in before 6pm today or risk being hit with a fine.
1.57pm GetUp! has an excellent breakdown of where the major and minor parties stand on the big issues. Check it out here
1:40pm: Voters in the Central Wheatbelt were out early on Saturday to cast their vote in the re-run of last year’s half senate election.
However, party supporters handing out how-to-vote information said the voters’ early start seemed to be driven more by the attitude of “let’s get this over and done with” rather than any enthusiasm for the poll or particular candidate amongst the 77 listed on the ballot paper.
Read the full story here.
1.30pm Voters turned out in their droves across the Federal electorates of Brand and Canning on Saturday, to mark their votes for Western Australia’s six new senators.
The Mandurah Mail was out and about at the polling booths in the area. Check out their photos here.
12:45pm: The WA Senate election is being re-run as a result of the High Court decision that declared last year's result void.
Justice Kenneth Hayne declared that because 1370 ballots disappeared between the vote and recount those voters were effectively "prevented from voting".
It is believed that some of the missing ballot papers were from the Bunbury East booth in Forrest.
12.00pm West Australians are heading to more than 700 polling booths around the state amid speculation that participation could be low due to voter fatigue.
Voters will elect six senators from 77 candidates, with the coalition, Labor, the Australian Greens, Palmer United Party and a raft of micro parties fighting for seats.
It is the third election in WA in just over a year after a state election in March last year and the September federal election, not including local government elections.
It seems like people were more interested in the polling booth sausage sizzle than casting their vote.
For more information about some of the 77 candidates who nominated for the April 5 election click here.