The People's Action Party (PAP) enters the first sitting of the new Parliament next week backed by the strongest electoral mandate it has received in 15 years.
The Workers' Party (WP), on the other hand, will be the only opposition party in the House, and with one representative less than in the previous Parliament.
The parties will have to prove themselves in different ways during the new term.
For the PAP, it is an opportunity for newly elected MPs and those who have been put forward to form the next-generation leadership to demonstrate that they are up to the challenge of taking the country forward, say observers.
"They have to show their mettle and display their leadership in policy defence and formulating new ideas that the younger voters expect of them," says Mr Inderjit Singh, an MP for 19 years before he stepped down at last September's general election.
For this reason, he adds, the older and more senior ministers should step back and allow their younger colleagues an opportunity to shine.
As for the WP - which had a breakthrough in 2011 by winning Aljunied GRC but came close to losing it at last September's general election - it needs to make its voice heard by taking stronger positions and championing alternative ideas, say analysts.
National University of Singapore sociologist Tan Ern Ser reckons that opposition parties, such as the WP, must provide the alternative voices and checks and balances Singaporeans expect. They must also champion creative, yet practical solutions to the challenges facing the country, and show themselves capable of municipal administration, he adds.
The year ahead
• Government: Set priorities for the term ahead - tackle a slowing economy and the job market; address the diversity of needs in society, from transport, healthcare and housing, to education, skills and the needs of the aged.
• PAP: Provide opportunities and showcase the next generation of leaders and newly elected MPs.
• Opposition: Demonstrate that they are in a position to offer and champion fresh and practical ideas and solutions, whether they are in or out of Parliament.
Two events in the first half of the year are perfect opportunities for both parties to set the tone.
First, the President's Address, to be delivered on Jan 15 at the opening of the new Parliament, will spell out the Government's agenda and programmes for its five-year term. MPs then have five days to debate the speech.
For the 19 elected MPs and two Non-Constituency MPs making their debut in the House, their maiden speeches will be a chance to showcase ideas, distinguish themselves and show what they stand for. The debate on the Government's Budget over two weeks in April will be a second early opportunity for them.
Mr Singh expects a robust debate: "We have quite a diversified group this time, especially among the backbenchers. Some already have areas of interest such as animal rights, volunteerism, youth engagement and the economy."
Another thing to watch will be how the dynamics will change in the House, given the disparity in the electoral showing of the two parties at the September polls.
There was a nationwide vote swing of 9.8 percentage points at the general election towards the PAP. Its share of the popular vote rose to 69.9 per cent and it won 83 of the 89 seats in Parliament.
They have to show their mettle and display their leadership in policy defence and formulating new ideas that the younger voters expect of them.
MR INDERJIT SINGH, a former MP, on the new PAP MPs and next-generation leaders
A post-election survey by the Institute of Policy Studies found that the biggest shift towards the PAP came from those aged 21 to 29, and those aged 65 and older.
Unlike the PAP, the WP gained no ground and saw its overall vote share fall to 39.8 per cent from the 46.6 per cent it received at the 2011 General Election.
The party lost the Punggol East single-seat ward which it won in a 2013 by-election, narrowly won in Aljunied GRC, and kept the Hougang single-seat ward with a reduced winning margin. This translates to six elected MPs and two Non-Constituency MPs .
Given the backing the PAP received and its dominance in Parliament, will the party be heavy-handed in its approach during the debates on the Presidential Address and Budget, and go on the offensive against the Opposition?
Professor Tan and Mr Singh do not believe so. Indeed, they reckon the PAP MPs may, paradoxically, take on roles that opposition MPs are expected to play.
"Voters gave an overwhelming mandate to the PAP, expecting the party to check itself on its own policies," says Mr Singh, who also hopes that some of the new MPs will question some existing policies and "not display group-think".
He adds: "If the PAP MPs don't have among them, some who are willing to challenge policies and the ministers, the electorate might feel short-changed and this will not be good for the next election."
Regardless of party lines, the issues confronting the Government and the new Parliament are going to be on a different track.
Unlike the hot-button infrastructural issues that emerged in the 2011 elections, the challenge facing this Government is to prepare the country for a slowing economy amid a bumpy and, arguably, uncertain global outlook.
This is why the Presidential Address and subsequent debate is worth tuning in to, say analysts.
Institute of Policy Studies senior research fellow Gillian Koh says: "Singaporeans who want to know what is in the pipeline and who want to see how the Government is responding to the views they have shared in past years should pay attention."