Asuncion - Paraguay has been governed by the Partido Colorado for 61 years, but the end seems near as the South American country prepares to vote in presidential elections on Sunday.

According to all opinion polls, former Roman Catholic Bishop Fernando Lugo, 56, is the main favourite, although many Paraguayans have expressed a fear that fraud may be used to preserve the status quo.

Lugo is the candidate of the Patriotic Alliance for Change (APC), a coalition of some eight opposition parties and a score of social movements.

This group of anti-Colorado organizations which span from the political left to conservatism has caused a stir. Indeed, the Colorados have been able to hold on to power since 1947, and especially since the end of the dictatorship of Alfredo Stroessner (1954-1989), among other things because the opposition was divided.

Now, however, not only is the opposition more united than before, but the Colorados too are fielding two candidates. The party's official representative is Blanca Ovelar, while former coup leader Lino Oviedo - also identified with the party - is standing as the candidate of the Party of the National Union of Ethical Citizens (Punace).

According to experts, these are the only two candidates that could yet trouble Lugo.

An opinion poll by the company COIN published one week before the election put Lugo ahead with 34.5 per cent of the expected vote. It also predicted a technical tie between Lino Oviedo, with 28.9 per cent, and Blanca Ovelar, with 28.5 per cent.

A simple majority on election day will be enough for the winner to be elected to succeed outgoing President Nicanor Duarte Frutos, with a five-year mandate.

COIN noted that the turnout will be key to Lugo's aspirations: the more people vote, the more chances the former bishop has to be the next Paraguayan president.

Until one year ago, Lugo was the bishop of the poorest diocese in a country with a poverty rate of 25 per cent. He does not define himself as a proponent of Liberation Theology, but rather as a centrist politician.

At the end of last year, however, he hinted that he has some affinity with socialism.

In terms of content, the leading candidates are not very different from each other. All of them vow to stand by the market economy, to respect private poverty and to promote private initiative. They say they will fight corruption and poverty more efficiently than has been done so far.

The main themes in a short campaign were, however, energy policy and agrarian reform.

Lugo favours re-establishing the country's energy sovereignty.

Paraguay is currently committed to selling to Brazil its surplus electricity from Itaipu - the largest hydroelectric plant in the world, managed jointly by the two countries - at prices far below those set by the market. Almost all candidates insist that this has to change.

Arable land in Paraguay is largely concentrated in the hands of a few large companies who are resorting more and more to soya farming. The 351 largest cultivators in the country own some 40 per cent of arable land in the country.

Amid debate on land reform, experts estimate that up to 150,000 landless families have been pushed to the cities by hunger.

Some 2.8 million Paraguayans are entitled to vote Sunday. Beyond the president, they are set to elect 45 new senators, 80 provincial legislators, 17 governors and 400 district councillors, as well as the country's representatives in the regional Parliament of the South American trade bloc Mercosur.

Voting is compulsory in Paraguay for anyone aged 18-75.

The landlocked South American country set between Argentina, Brazil and Bolivia has a GDP of 9.3 billion dollars - although a very large informal economy makes exact figures difficult - which grew by 4.5 per cent last year. Paraguay exports mainly commodities and has profited from the surge in their prices in recent years.

It has a population of 6.8 million, of which over 1.5 million live in the capital, Asuncion, and its metropolitan area.

Paraguay became independent from Spain on May 14, 1811. (dpa)