As Mexico prepares for the presidential inauguration of Felipe Calderon on 1 December, the BBC's Duncan Kennedy in Mexico City reports on the challenges the conservative politician faces.
Over the din of Mexico City's incessant traffic there is another, more alluring, noise. It is the haunting sound of whistles and you can hear them everywhere.
The new president has been trying to stamp his authority
They come from the city's knife sharpeners. They whistle, you bring out your knives. Porfillo Martinez is one of them. His multi-tonal whistle is audible from several blocks away. Porfillo has been putting exquisitely sharp edges to the blades of the capital's cutlery for 27 years.
He has attached a circular grinding stone to the back of his bicycle. He props his bike onto its stand and then, using the pedals, he spins the stone and applies the edge of the knife. As he does it, he talks politics - presidential politics.
"I'm just not sure about Felipe Calderon," he says.
"I don't think he's for Mexico's poor people who worry about the price of milk and petrol," says Porfillo, who earns less than US$10 (£5) a day.
Mexico has a thriving middle class, but there are something like 40 or 50 million Mexicans who are classed as poor. They do not tend to have jobs or much money. Felipe Calderon says he will make them a priority.
He has already talked about improving pensions for older poor people and easing the tax burden on others. He also has a pretty healthy economy on his side, with low inflation and modest growth.
But in the past six years or so, millions of Mexicans have given up on their country and headed north to the United States.
One joke doing the rounds here is that the outgoing President, Vicente Fox, created six million new jobs as president. Trouble is, they say, they were all in California.
That might be unfair on Mr Fox, but Felipe Calderon does not want to be the butt of similar jokes.
He knows he has got to attract more foreign investment, from the United States and elsewhere.
The British engine company Rolls Royce has been here for decades. Now run by Robert Hickman, it is doing a thriving trade, with business over the next year worth up to a US$1bn.
"I'm cautiously optimistic about a Calderon presidency," says Mr Hickman.
Fighting in Congress: A sign of what lies ahead?
"He's got to tackle the country's near-monopolies in telecommunications and in oil," he says. "Otherwise we're going nowhere."
Surrounded by pictures of Rolls Royce engines and the front grilles from the vehicles of its famous car-making cousin, Mr Hickman is clear about what Mr Calderon must do.
"He may not be very charismatic," he says. "But he's a clever man and will need to stamp his authority quickly."
For the past few days, the new president has been trying to stamp his authority by naming his cabinet. Mostly free marketeers and mostly men like himself, his team has drawn a wide range of generally positive views from commentators.
They are going to need some pretty deft political footwork to get their laws passed through Congress.
One sign of what might lay ahead came this week when deputies in Congress started laying into each other with punches.
It wasn't exactly the stuff of Mike Tyson, and there weren't any knockouts. But, to some, it was a points victory for Mr Calderon's left-wing opponents and their plan to disrupt his presidency.
The undisputed king of the ring when it comes to disruption is their leader Andres Manuel Lopez Obrador.
Having lost the election for the presidency, an angry Mr Lopez Obrador called thousands of his supporters onto the streets and has recently declared himself Mexico's "alternative" president.
It has raised laughs and eyebrows in equal measure in conservative sectors, but Mr Calderon cannot afford to ignore this seasoned political operator.
"Lopez Obrador should be the new president," says Francisco Gonzalez de Cossio, a former Mexican ambassador to Saudi Arabia and Jordan and supporter of the defeated candidate.
"It was fraud and Calderon should not be taking over office," he says.
"I'm not optimistic about a Calderon presidency. He won't look after the poor, just the powerful, who steered his way to victory.
"The jury is out on him."
Mr Calderon will also have to prove himself in other ways.
Take the Oaxaca dispute.
The Oaxaca dispute will be a test for the new president
Oaxaca is a city in southern Mexico famous for its beautiful colonial buildings. Or it would be if you could still see them.
You cannot because they are now hidden under layers of graffiti, the work of demonstrators campaigning there for the past six months.
Up to 15 people have died in the dispute over who should run the local government. Federal riot police are now encamped in the city.
Resolving Oaxaca will test all of Mr Calderon's persuasive skills.
Crime is another persistent issue in Mexico. Around 2,000 people have died in the violence between drug cartels, all vying to supply the lucrative US market.
Relations with his northern neighbour will take up much of Mr Calderon's time in office.
In recent months, they have been put under strain by Washington's plans to build a wall along key sections of the between the two countries. Although doubts have been raised about whether it will actually be built, it has gone down very badly here.
There is a sense of disappointment that Mexico isn't treated more like a friend, especially since there is no evidence any terrorist has crept into the United States across its southern frontier.
It all adds to a sense of anxiety here. The feeling that the place isn't settled.
It did not help that Mr Calderon failed to secure a resounding mandate from the voters.
The election may have been five months ago, but the question of fraud is still raised here by his left-wing opponents. They will not let him forget it.
Felipe Calderon is an energetic, charming, man with a deep commitment to his Catholic faith. But he will have to watch his back, otherwise his enemies may soon be whistling for their own metaphorical knife sharpeners, to make his life extremely uncomfortable.