National's great fear will be the wedge politics Peters deployed with such devastating effect in Northland spreading to other provincial regions. That strategy involved pitting Auckland against the "neglected" regions. In his speech in the general debate yesterday, Peters made it clear he was intent on seeding that in other regions.
Having eked out a political living for so long by relying on the votes of the fringe, Peters is reinventing himself as the friend of the provinces, the farmers, the rural sector. He is putting out a slate as the home of the anti-Auckland vote. "It's not all about Auckland," he cried. He is making a clear pitch into National's provincial heartland. For that reason, Peters is already deflecting any suggestion he might owe Labour.
National has a fine line to tread in dealing with Peters and Northland. National will be wary of a backlash in other provinces if it is seen to favour Northland in its bid to get the seat back. It also knows Peters will claim the credit for anything it does in Northland.
It is not all good news for Peters. During the byelection campaign, National was frustrated Peters' promises were not as heavily scrutinised as its own. The reason for that was precisely the reason National gave as to why people should vote for them instead of Peters: because they were in government.
Peters highlighted his own impotence in that regard on the first day back in Parliament. He swaggered into the House, said, "Boo", and then asked Key when he would announce all the policies for Northland that National held back during the campaign. Key simply replied that they would be revealed in the "fullness of time" and Peters was powerless.
Key's point was made: National still holds all the cards there.
So he has made noises about working with National, albeit only on "sane and rational" ideas. As with beauty, sanity and rationality are in the eye of the beholder, and Peters and Key are very different beholders. The cha cha cha is unlikely to end in a graceful dip.
In some respects, Peters has created a rod for his own back. He will now have to deal with the gripes and issues 45,000 constituents can muster up among them - work that does not get headlines. Such is the lot of an electorate MP.
Come 2017, Peters will be torn between campaigning in Northland and the nationwide campaign as party leader.
He holds Northland now but it is by no means a safe seat, and certainly not one he can rely on enough to neglect the 5 per cent vote NZ First will otherwise need to return to Parliament. It will help Peters that National's tide will likely be ebbing by then. But he cannot ignore the conservative rump in the electorate. The left is not enough to get him there alone.
Just how hard holding that seat is will partly depend on who National selects to take him on. Mark Osborne was a decent enough fellow. But Northlanders relish colourful, flawed MPs. Shane Jones, Hone Harawira, Dover Samuels, John "Hone" Carter and now Peters are all Northlanders.
Peters' 21-year hold on the Tauranga seat was wrested off him in 2005 by Bob Clarkson, who had a high local profile and blunt turn of phrase. Clarkson was not the safest candidate. He used his left testicle as a betting chip. He didn't last long with his rather outdated views. But he was colourful and you fight fire with fire, not a chartered accountant and a raft of statistics.