Coming at the worst possible time for both Tony Abbott and Bill Shorten, the byelection might be seen as an unpopularity contest between the two leaders.

Who do we despise the least? It's a tough call, but Labor and Liberal will be spending big money to find out.

Both leaders have sailed troubled and murky waters these last few months.

The government has taken on water from its handling of the resignation of speaker Bronwyn Bishop and Bill Shorten has faced tough questioning by the royal commission on union corruption.

Both sides are now facing voter backlash over accusations of abusing travel entitlements.

But the byelection in Canning will be more than just a test of leadership muscle.

Candidates are far more important in byelections than general elections.

In an up-close-and-personal byelection, voters get a better chance to know the hopefuls.

Political circles have been buzzing with reports the late Don Randall's daughter, Tess Randall, may nominate for Liberal endorsement.

This makes sense for the Liberals. Don Randall was well liked in the local community and his daughter may attract a sympathetic vote, particularly if she is as hard working as her father.

However, Tess Randall is relatively young and needs to campaign hard to establish her credentials. Although she is a staffer for Foreign Minister Julie Bishop, it is unclear how she would stake a claim to the job.

One thing is certain: with the name Randall, voters will be all ears.

Labor hopeful and Law Society President Matthew Keogh, also a former junior staffer for Alannah MacTiernan, has the opposite problem.

On paper, it is understandable why Labor hardheads might toy with his candidacy.

But what a Terrace lawyer who lives in Perth's leafy inner suburbs has in common with the people of Mandurah is anyone's guess.

In a contest where all politics is local, Keogh would begin the race with zero local profile.

Whoever wins the nominations, both parties are desperate for a good showing.

Abbott survived an attempt on his leadership in February and the latest Fairfax poll shows Shorten pulling ahead as preferred prime minister.

Many inside Labor believe Shorten would struggle under serious political pressure, the kind Abbott has not yet had the clear air to exert.

Either way, both parties will be sinking in serious campaign cash to bolster their chances.

Let's hope it's the people who end up the real winners on election night.

Nathan Hondros will be reporting the Canning byelection for the Mandurah Mail. Tips to nathan.hondros@fairfaxmedia.com.au or @nathanhondros on twitter.