Change is a powerful political ally, especially when things are not going so well. As with the US presidential election, candidates in the 62nd Italian postwar election are keen to show they can break with the past. Italy will have a new leader by the time votes cast in the two-day general election are tallied on Monday evening. But it is far from certain whether either candidate is willing, or able, to change Italy enough.

It is a two-horse race. If Silvio Berlusconi is elected, Italy will call time on the centre-left coalition that has ruled the country under Romano Prodi for the past 20 months. Mr Berlusconi is a man Italians know well, having served as Prime Minister twice before, most recently from 2001 to 2006. The 71-year-old billionaire and media tycoon has fame around the globe, too, although not always for the right reasons.

Italy needs to reform its public services and tackle trade union power if it is to regain economic prowess. By instinct, Mr Berlusconi will pursue pro-market reforms that came to Britain under Margaret Thatcher 25 years ago. As rubbish piled in the streets of Naples, it was easy to draw parallels between the 1978-79 winter of industrial discontent in Britain and Italy's version more than a quarter of a century later. But Italians may doubt whether Mr Berlusconi can act on his instincts. Mr Berlusconi blames Italy's anaemic economic prospects on the socialist proclivities of Mr Prodi. Yet the failings now apparent are at least partly due to the inadequacies of Mr Berlusconi's previous terms in office. His populist instincts, meanwhile, are worrying. Some may forgive his demeaning comments this week about the physical appearance of female political opponents as harmless banter. It is much more difficult to dismiss his assertion that senior members of the Italian judiciary should take mental health checks. It is unlikely to help him to win support for reform from the legal establishment.

If Italians vote for Walter Veltroni, the centre-left candidate, they will get generational change in the form of a first-time prime minister 20 years younger than the old pretender. But in terms of political complexion it will be more of the same. He and Mr Berlusconi have gravitated towards the Centre, and share views - in theory if not in practice - on key issues such as controlling public expenditure. Measures from Mr Veltroni to make it easier to start up a small business have been well received. His determination to curtail public spending is welcome. But his ability to change Italy will be hindered because he will rely on backing from old-style Communists.

If the most recent opinion polls are to be believed, Italy will give Mr Berlusconi a last chance to deliver on the tantalising promises that he has made. But the most recent polls are two weeks out of date, and anecdotal evidence suggests that Mr Veltroni has narrowed the gap. This is an achievement in itself, given the distrust of the Left created as Mr Prodi attempted to improve public finances by raising taxes.

A win for Mr Berlusconi is likely to make Italian politics more memorable, and perhaps more entertaining. There is no guarantee that Italy will improve in the way it needs to if he regains power. It must pursue reform with gritty determination and a new vigour. Italians would surely be wise to choose the devil they don't know, Mr Veltroni, over the devil they do.