The fate of the Western Australian Senate election will hang in the balance today when the Court of Disputed Returns sits in Melbourne.

The court has been asked by the Australian Electoral Commission (AEC) to find the poll void, so it can mount a rerun.

The case comes after the embarrassment to the AEC over the loss of 1,370 ballot papers after last year's September election.

The votes were discovered to be missing when a recount was ordered, after a challenge by two of the candidates, the Green's Scott Ludlam and the Sporting Party's Wayne Dropulich.

The dispute is over the fifth and sixth Senate positions.

In the initial count which included the lost ballot papers, the winners were Labor's Louise Pratt and the Palmer United Party's Zhenya Wang.

The pair had won on preferences from a losing candidate, the Shooters and Fishers Party's Murray Bow.

But the results were very close and on the recount the Australian Christian Party's Jamie Van Burgel was ahead, and his preferences led to the election of Senator Ludlam and Mr Dropulich.

Greens want election re-run despite win

Despite winning, Senator Ludlam says it would be hard to argue the result should stand because so many ballots were lost, and he is looking forward to a re-election.

"There's no question it would be a really unique opportunity to see federal politics filtered through a Western Australian lens for a change rather than everything being from an east coast perspective," he said.

"And the fact is, Tony Abbott's extreme unpopularity in this state, compounded with the disastrous performance of the Barnett government, means that it probably would be a very different result."

He says an election re-run might prove difficult for the Liberals.

"Since the change of government we've seen the performance of the Abbott government doing so much damage, just the attacks on the renewable energy industry and jobs in that industry alone, and it's been really difficult to really knuckle down and get to work when we don't know what the future holds for any of us so I really am hoping that it gets resolved this week, if possible," he said.

The Australian Sports Party is taking a different tack with Mr Dropulich saying they will argue the result should stand.

"Obviously we'd like the current scenario to stand and for me to be staying as a senator, and that'd be the ideal situation for us so there'd be no re-election so we wouldn't have to go back to the polls and we can move forward," he said.

"It's been a roller coaster ride up and down and now it's just a matter of waiting and see what happens with the High Court."

The AEC says its inability to include the missing votes has affected the election, and that is why it wants a fresh poll.

So far the missing ballot papers have not been found, despite an inquiry by the former Australian Federal Police commissioner Mick Keelty.

Mr Keelty was particularly scathing of the management practices at the AEC but could shed no light on where the missing votes might be.

Today's hearing will focus on three key questions: whether voters who lodged the missing ballot papers were prevented from voting; whether the court is prevented from considering any evidence suggesting how those voters voted; and whether there could be a further inquiry into the AEC's decisions on votes deemed informal during the counting.

The AEC argues the voters were prevented from voting, and the Court of Disputed Returns cannot consider other information.

There is strong support for voiding the election.

The Labor Party would like the first count to stand, and if not then the election should be held again.

But a submission from the three Liberal Senators, who have secured seats in the first four spots, suggests a fresh election should be a matter of last resort.

Outcome will have political consequences and also impact confidence in AEC

Justice Kenneth Hayne will preside over today's hearing, with submissions are expected to take two days.

After that Justice Hayne has several options, including ruling the poll void on the spot, referring the three legal questions to the full bench, or even referring the matter to the Federal Court.

Just when a new election would be held remains unknown, but the court is under some pressure to deliver a timely result, before the new senate sits in July.

The important thing about today's case has as much to do with confidence in the AEC as it has with the makeup of the senate.

The whole affair of the missing votes has been deeply embarrassing, and forced Commissioner Ed Killesteyn to apologise in the face of strident criticism.

And there will be political consequences.

The Senate has 76 members. When the new senate sits in July the Abbott Government will need 39 votes to pass legislation, but will have only 33.

The outcome of the case obviously will not change the government, but in a Senate dominated by minor parties and independents, the outcome could change the equation on important issues.

The Abbott Government, which secured three senate spots in Western Australia, will be watching closely.