By Steve Kingstone
BBC News, Sao Paulo
The boxing metaphor sometimes wears thin in politics, but in the case of President Luiz Inacio Lula da Silva it remains wonderfully apt.
From his childhood in Brazil's impoverished north-east, to his defiance of the military government as a trade union leader, Lula is a man who knows the meaning of struggle.
The pugilist president reached out to voters across Brazil
Last year, he was knocked to the canvas by a cash-for-votes scandal and during this election, allegations that his Workers Party had engaged in dirty tricks again had him on the ropes.
But both times Lula recovered, and where it matters most - with the voters - he is now the undisputed king of the ring.
Two electoral regions decided this contest. Firstly, the northeast, where incomes are the lowest in Brazil but also the fastest-growing, thanks to Bolsa Familia, Lula's headline welfare benefit.
The president won big in his home region, increasing his share of valid votes from 67% in the first-round to 77% in the second.
Not only did he pick up support from defeated first-round candidates, he also took votes from the challenger, Geraldo Alckmin.
Attack adverts had portrayed Mr Alckmin as a cost-cutter who might scrap Bolsa Familia.
But if Lula's victory was planted in the north-east, it was harvested in the south-east, which with 55 million voters is home to almost half of Brazil's electorate.
The region includes the state of Sao Paulo, which until recently was governed by Mr Alckmin.
In round one, the challenger had secured a narrow regional lead, but on
Sunday Lula took the Southeast by 57% to 43%.
With the President victorious in Brazil's two most populous regions, the contest was over.
So what brought south-eastern voters back to Lula? The lack of fresh corruption claims was certainly a factor, enabling the president to get back on the front foot.
His strategy of attacking Mr Alckmin on privatisation also paid off, forcing the challenger to waste precious campaign energy denying that he planned further state sell-offs.
But perhaps more than anything, the four weeks between the two rounds of voting witnessed a simple restoration of equilibrium.
Geraldo Alckmin was accused of planning privatisations
For months, the opinion polls had given Lula a big lead, with most Brazilians agreeing that Brazil was moving broadly in the right direction.
After a brief presidential poll dip - coinciding with the dirty tricks scandal - normal service was resumed.
Some wonder whether an emboldened Lula will now "go left", in the style of Venezuela's President Hugo Chavez or Bolivia's Evo Morales.
If that means re-nationalising former state enterprises or expelling unwelcome foreign companies, forget it.
Lula's heart may beat to the left, but his head tells him foreign investment is essential for Brazil to grow.
If, however, going left means investing more in land reform, university scholarships for the poor and redistributive welfare programs, then yes.
Narrowing Brazil's wealth and opportunity gap is the guiding principle of Lula's presidency - the only question is how much is he willing to spend on it?
In the coming days, keep an eye on the kind of parliamentary alliance the president forms.
Lula's policies promised to help Brazil's poorest
If he is serious about tax and pension reforms - which most commentators agree are prerequisites for faster growth - he'll need a hefty majority in congress.
Listen out, too, for the tone of second-term foreign policy. Will Lula resume Brazil's pretensions to regional leadership, especially if that means butting heads with Mr Chavez?
Or might he join the Venezuelan in the kind of anti-American alliance that Caracas craves? Washington, which regards Lula as the moderate face of Latin America's left, will be paying close attention.
Finally, the corruption and dirty tricks allegations may not have prevented
Lula's re-election, but they still have the potential to do damage.
The police are investigating the origins of $800,000 (£423,000) with which Workers Party sympathisers apparently tried to buy documents smearing political rivals.
Until now, the scandal has not touched Lula himself. But if the money trail leads anywhere near the presidential palace, he'll have a renewed fight on his hands.