Four months ago, it was a much simpler time on Capital Hill.

Scott Morrison had just handed down his first budget, and Malcolm Turnbull had asked Governor-General Sir Peter Cosgrove to do his constitutional duty and kick out the entire parliament because of an unruly Senate.

But so much has happened since then, and this week Parliament returns after a 116 day hiatus.

Gone are the days where the Government could expect the party position would always prevail, just because of its sheer weight of numbers.

The Coalition commands 76 votes in the House of Representatives, a majority of one solitary member — it has left Mr Turnbull's clasp on power weakened.

State of Play: House of Reps Coalition: 76

Coalition: 76 Labor: 69

Labor: 69 Katter's Australian Party: 1

Katter's Australian Party: 1 Nick Xenophon Team: 1

Nick Xenophon Team: 1 Greens: 1

Greens: 1 Independent: 2

Two of the five crossbenchers, Bob Katter and Cathy McGowan, have given Mr Turnbull their support on matters on confidence and supply.

But as for the rest of the parliamentary process, it can probably be best described by the man in the Akubra from north Queensland.

"You try running a government with one vote up your sleeve," Mr Katter said.

"Don't have your mother die because you can't go to the funeral — don't go to the bathroom."

Scott Morrison and Malcolm Turnbull on May 4, the day after the budget was announced. ( ABC News: Nick Haggarty )

Coalition's slender majority will be tested

The first test could come in the form of a topic many people either do not care about or fully understand, until they get to the end of their working careers — superannuation.

Coalition backbenchers have turned their nose up at the Government's plan to cap the tax concessions for high income earners, and Queensland LNP member George Christensen has already threatened to cross the floor if there are no changes.

The Government has also announced plans to haul banking executives before a parliamentary committee for a "please explain" every year.

That is not good enough, according to the federal Opposition, who maintain their calls for a royal commission into the banking sector.

It will be interesting to watch what tactics Labor use in the Lower House to try and test Mr Turnbull's leadership and the Coalition's slender majority.

There are 39 fresh-faced politicians joining the House of Representatives. ( ABC News )

The nation could see parliamentary motions to suspend standing orders during Question Time used with regular and frustrating frequency.

The Government's "omnibus" bill will be introduced, containing more than $6 billion in savings measures Labor agreed to in the dying weeks of the election campaign, as well as legislation to protect volunteers after the bitter CFA dispute in Victoria.

Government will need nine senators to pass legislation

The Senate is an even more interesting prospect, after the double dissolution, designed to get rid of an unruly crossbench of eight senators, returned a grab bag of 11 senators, from a wider variety of backgrounds.

State of Play: Senate Coalition: 30

Coalition: 30 Labor: 26

Labor: 26 Greens: 9

Greens: 9 One Nation Party: 4

One Nation Party: 4 Nick Xenophon Team: 3

Nick Xenophon Team: 3 Liberal Democratic Party: 1

Liberal Democratic Party: 1 Family First: 1

Family First: 1 Jacqui Lambie Network: 1

Jacqui Lambie Network: 1 Justice Party: 1

Pauline Hanson returns to Parliament 20 years after her maiden speech in the Lower House, this time as a senator.

She will be joined by another three members of her One Nation Party.

Nick Xenophon has capitalised on his personal popularity in South Australia to bring another two members of his team to Canberra, while David Leyonhjelm, Jacqui Lambie and Bob Day survived an attempt on their political lives.

The "Human Headline" Derryn Hinch will swap the studio for the chamber, in his new role as a senator for Victoria.

The Government needs the support of nine senators to pass legislation.

If Labor and the Greens join forces, they only need to convince three senators to cause grief for the Coalition.

One Nation Senator Pauline Hanson talks with fellow crossbencher Derryn Hinch. ( ABC News: Nick Haggarty )

The Prime Minister says he has already had constructive discussions with a number of the crossbenchers.

He has even appointed people within his office to be special liaisons and help make the road to consensus a bit smoother.

It is likely to liven up debate on the piece of legislation that sent the nation to a double dissolution election — plans to reintroduce the Australian Building and Construction Commission (ABCC).

Combine that with a renewed push from the conservative elements of his party to water down parts of the Racial Discrimination Act — that proposal has support from a number of crossbenchers.

Throw into the mix the ongoing debate about the merits and timing of a plebiscite on same-sex marriage, and the timing and question to be asked at a referendum on recognising Indigenous Australians in the Constitution, and there is plenty of argy-bargy to captivate the nation still to come.

One thing is for sure — the 45th Parliament will be very, very interesting.