Now he's poised to form his government, and after that reality sets in.
He has said he will "fix the economy". He has said the broken health service will be repaired. He has said he will ensure that people who work hard will be able to get ahead.
Poor education results will be turned around, the country will be "back on track".
Voters who have taken him at his word, and given him the chance to be prime minister, will expect him to deliver.
After all, one of his main complaints about Labour was that it didn't deliver. Luxon has said he knows how to, because that's what he's done during his working life as a chief executive.
It's going to be fascinating to watch, and it wouldn't be surprising if the new government soon comes up with an assessment we've heard before when there's been a change: "This is going to take time".
The opposition will be onto it. National's promises to fix nearly everything that isn't working properly will be measurable, from hospital waiting lists to exam results.
Labour has its own crisis, a really big one. How did it lose bedrock electorates as it slumped to defeat - and two of them to the Greens?
The red tide of 2020 has been reversed, sweeping away seats Labour has held for decades including the "red wall" of Auckland seats that have gone to National.
Labour started bleeding votes to the Greens after its leader Chris Hipkins made his captain's call to ditch the wealth tax policy, which upset many left-wingers.
The party's post mortem could show that decision may have been a turning point, and that it worsened the devastation.
Another stunning scenario has been Te Pāti Māori's success in the Māori roll seats.
Who could have foreseen Nanaia Mahuta being defeated by a 21-year-old, Hana-Rawhiti Maipi Clarke?
Astonishing as these results may be, attention will soon switch to Luxon and what the new government is going to look like.
As RNZ reported, the majority that National and ACT hold is so slim that Luxon will very likely have to go to Winston Peters, who has brought NZ First back to Parliament with eight seats.
The final picture is not clear because special votes still have to be counted and results are preliminary. National could lose or gain a seat, but whatever the final count is the majority will still be uncomfortably small.
During the campaign Luxon said he didn't know Peters.
He soon will, and might wish he didn't. Peters is a very tough negotiator, he will push hard for his party's policies to be implemented. It won't be easy fitting NZ First into an arrangement that includes ACT.
With the exception of Labour, which has taken a thrashing, all the parties had something to celebrate.
The Greens increased their share of the party vote from 7.6 per cent to 10.8 per cent and their seats from nine to a projected 14.
What really delighted the party was winning, on preliminary results, Wellington Central and Rongotai. With Chloe Swarbrick retaining Auckland Central, the Greens will have an unprecedented three electorate seats in the new Parliament.
Previously, it has never held more than one.
ACT's big success was deputy leader Brooke van Velden taking the previously safe National seat of Tamaki from Simon O'Connor. With David Seymour retaining Epsom, the party has two electorate seats and 11 in total compared with nine in the previous Parliament.
Te Pāti Māori doubled its seats from two to four. It previously held just one electorate seat, and has taken three from Labour.
By Peter Wilson
*Peter Wilson is a life member of Parliament's press gallery, 22 years as NZPA's political editor and seven as parliamentary bureau chief for NZ Newswire.
