Despite ruling Argentina for all but two of the last 24 years, the national headquarters of the Peronist party in Buenos Aires is a strangely forlorn place.

Though crucial mid-term elections are looming, the building is eerily quiet and a porter suggests that as no one is currently available, requests for an interview with party officials, the reason for the Irish Times' visit in the first place, be made over the phone. Except the party's phone number always rings out while emails go unanswered.

The Peronist movement though is far from exhausted after its long stint at the helm of this South American nation. Tomorrow, a list of its congressional candidates is set to top the poll in the strategic province of Buenos Aires, home to 37 per cent of the country’s electorate.

Most likely, in doing so it will beat a rival group of Peronists loyal to Peronist president Cristina Kirchner into second place.

Over the past decade, national elections in Argentina have become a battleground between various competing factions of Peronism, with the rest of the country’s political parties often reduced to the role of frustrated also-rans.

In the 2003 elections, that elevated Kirchner’s late husband Néstor to the presidency while three Peronist candidates took more than 60 per cent of the poll between them. Christina Kirchner won the next two disputes on the first round despite dissident Peronist candidates competing for a double-figure share of the movement’s votes.

Mid-term elections, especially in the Peronist heartland of Buenos Aires province, have witnessed particularly nasty contests between competing Peronist factions; the campaign ahead of tomorrow’s vote has proved no different.

After 10 years at the head of Peronism, the Kirchner grouping is starting to see power slip from its grasp. The president's list of candidates in Buenos Aires province is trailing to the rival Peronists grouped around the young photogenic mayor of Tigre, Sergio Massa.

A former Kirchner loyalist who served as the president’s cabinet secretary, he is now leading a “Renovation Front” that is hinting at a more moderate direction for Peronism after the strident populism of the Kirchner era, with promises to work more closely with business and crack down on rising crime levels.

He is seeking to capitalise on the fears of the Peronist party barons that the president's declining popularity puts at risk the movement's chances of holding on to the Casa Rosada in 2015. He has made little secret of his own ambition to run as the next Peronist candidate for president, despite a thin resume and his relative youth at just 41 years of age.

A win for Massa tomorrow would likely end any hopes of Kirchner being able to revise the constitution to allow her to run for a third term in 2015. That has earned him the hatred of some of the president’s supporters. Massa has been physically attacked while campaigning in Kirchner strongholds. His aides even mutter darkly about plots to assassinate him.

Kirchner's aides rubbish such claims and hope her convalescence from brain surgery might boost the chances of Martin Insaurralde, her hand-picked candidate, to run against Massa in Buenos Aires at the head of her own Peronist faction, the Victory Front.

Massa's political trajectory carries echoes of the Kirchners' own. In the 1990s, Kirchner and her husband Néstor were loyal supporters of President Carlos Menem, only to run against him in the 2003 election with a promise to break with his right-wing policies they had helped implement.

“Peronism is turning into its own opposition,” says historian Samuel Amaral, “but this has happened in the past. In the 1970s, Peronist trade unionists and Peronist guerrillas fought each other.”

Should she fail to halt the Massa bandwagon, Kirchner might be forced to turn to Daniel Scioli as her chosen successor in 2015. The former speedboat racer served as her husband's vice-president and as governor has run Buenos Aires province. His huge popularity based on a warm, easy-going personality has at times earned him Kirchner's enmity.

A deal though to succeed her could help preserve part of her legacy, increasingly under attack amid mounting economic problems.

Scioli recently called a meeting of Peronist barons at the party’s national headquarters, a clear signal of his own desire to lead the party in 2015. Where he would lead them is unclear. In the 1990s he was a loyal Menemista, over the last decade a loyal Kirchnerista.

For most of the party bosses who answered his call, such ideological questions are secondary. If Scioli can convince them he is the best bet to keep the movement in power, he will be the man to beat in 2015. If not, the bosses’ attentions will increasingly turn to Massa.