So have the parties, therefore expect to be mobbed by volunteers of all political hues this weekend as they make the final surge towards polling day.

Party volunteers will be on a binge of door knocking, cold calling and loitering around supermarkets, keen for a word.

If Abbott succeeds in becoming prime minister, the key issue for the national capital is how deep and fast he will cut the public service.

The corollary is clear - what impact will that have on the broader ACT economy?

Would the flow-on effect plunge Canberra into recession, as the Coalition's critics warn?

While that is not a live issue elsewhere, the scare campaign is at the heart of the battle in the ACT for the territory's two Senate seats.

We know one will go to Labor's Kate Lundy but will Zed Seselja retain the Liberal spot?

The former ACT opposition leader has a very good chance of gaining a new job, after toppling incumbent Gary Humphries in the party's preselection ballot.

Seselja has a very high profile in the territory following his strong campaign in the ACT Legislative Assembly election last year.

However, a difference in this Senate race is that the Greens' challenge is led by an experienced campaigner, Simon Sheikh, former head man at the GetUp! advocacy group.

He has attracted hundreds of volunteers, an army of enthusiasts who are building a real contest for the seat.

Sheikh says the ACT Greens have 1800 volunteers on their books but others come into his office to grab a few flyers to distribute in their neighbourhoods.

''From what we're told, it's the largest campaign that anyone has ever run in the ACT,'' he says.

The quota for a Senate spot in the ACT is one third of the vote.

The Liberals' core support in Canberra means the party has always held the second spot.

Margaret Reid was forced to rely on the preferences of One Nation but Humphries gained a quota at each election.

How much will Abbott's plan to reduce the public service affect Seselja's vote? And what about simmering resentment at the way Humphries was treated?

Some Liberal supporters might be tempted to switch to the Greens or Labor but there is no way the hard core will wobble. Another factor in the Liberals' favour is that Labor has already done a good job of undermining its scare campaign by its pre-emptive strike on the public service.

Lundy has been juggling her travel around the country as a minister, with her campaign in the election.

She says Labor cannot justify spending much money in the ACT when it is fighting to retain marginal seats around the country, but the interest in the Senate race boosts her profile.

''I'll never take it for granted,'' she says. ''I work really hard to maintain a presence and to compete with massively funded campaigns on behalf of the Liberal Party and the Greens so I am never in a position where I feel comfortable.''

The bottom line in this Senate race is the Greens are a force to be reckoned with.

The party picked this fight because of just how tight the race is.

They had a boost with the draw for the ballot paper, gaining third spot, where the party may benefit from the preferences of minor parties.

The Liberal and Labor parties have been relegated to the tail end of the 13-position ticket.

In the 2010 election, the quota to win an ACT Senate spot was set at 76,423.

Labor's Senate group voting ticket received 93,639 first preference votes, with 76,463 for the Liberals and 52,546 for the Greens.

The Greens signalled how important they regard the ACT as an electoral battleground by holding their party's national launch here last Saturday.

They are effectively treating the ACT Senate race as a marginal seat campaign.

Sheikh's message is that installing him in the Senate could be the vital circuit breaker to the Coalition's plan to gain control of the upper house.

However, if Seselja triumphs, and the Coalition wins the election, his first term will be difficult.

Public service numbers would be reduced by 12,000 by natural attrition.

As well, the Coalition wants to send public servants to northern Australia, and one agency to Gosford.

Coalition figures would be boasting, around the nation, of how they were ''cutting the waste'' in Canberra.

Seselja would have to fashion himself as Canberra's champion, fighting from inside the government to ameliorate damage without creating enemies in the leadership team.

He believes that once the budget was restored to surplus, Canberra would reap the benefits, referring to John Howard's record of building the National Museum.

''So that's the flip side, when you get the budget under control Canberra does very, very well,'' Seselja says.

The three lead candidates in the ACT Senate race have been devoting many hours to campaigning - attending functions, door knocking and at shopping centre stalls - and it's been cold work.

Along with the main parties, there's plenty of choice for ACT voters.

The Animal Justice Party has first place on the ballot paper, therefore benefiting from the so-called donkey vote.

The Rise Up Australia Party is standing here, as well as the Palmer United Party, Katter's Australian Party, the Stable Population Party, Bullet Train for Australia, the Sex Party, Drug Law Reform and Philip Nitschke for the Voluntary Euthanasia Party.

One reason the focus of Canberra's voters is the Senate race is that the results in the ACT's two lower house seats - Fraser and Canberra - are pre-ordained by the electoral boundaries.

Both seats are safe Labor fiefdoms and there is no change on the horizon.

Those results will pop up early next Saturday evening but it might be a long wait for the Senate figures - especially if it's a close race - to learn if the Greens have succeeded in their aim to shake up the ACT Senate race.