Sandy Gill in Sofia -

It's not been an auspicious start to the election campaign for the just-resigned governing party. With parliamentary polls scheduled for May 12, Citizens for the European Development of Bulgaria – GERB is its Bulgarian acronym – is trying to engineer what would be a first in post-communist politics in the Balkan state: a second term as the dominant force in government.

That would be quite a feat, considering that GERB, in government since 2009, stepped down on February 21 in the face of mass protests at high electricity bills that went broadly political (and very slightly violent), with its mouthy and popularity-hungry premier Boiko Borisov falling into uncharacteristic near-silence for more than a month thereafter. But Borisov has become talkative again and, with opinion polls unexpectedly favourable for him, the election campaign kicked off formally on Friday, April 12.

Things haven't gone too well for GERB so far. Over the first weekend of the campaign, attempting simultaneously to emphasise his government's welfare achievements and the erosion of the country's reserve position, Borisov contrived to remark that "pensioners had eaten up the fiscal reserve" – a formulation gleefully pounced on by opponents.

And on April 12 came news from the prosecution affecting Borisov's key henchman Tsvetan Tsvetanov, interior minister in Borisov's cabinet and now head of GERB's election campaign staff. Tipped off at the end of March – with information routed through (and well publicised by) Socialist opposition leader Sergei Stanishev – chief prosecutor Sotir Tsatsarov let loose a team of prosecutors to look into allegations of illegal phone-tapping by the interior ministry of a bewildering range of business figures and politicians (including some of GERB's own ministers).

Tsvetanov dismissed the allegations as nonsense, promising to resign if they proved true. Opposition figures duly called for him to make good on his promise when on April 12 the prosecution announced that charges would be filed against four interior ministry officials - three for failing to lay down proper surveillance guidelines and one for destroying evidence. These officials were Tsvetanov's responsibility, argue the opposition, though there's no sign so far of him doing the honourable thing. But the affair – inevitably dubbed "Bulgarian Watergate" – will add heat to what already promises to be, well, quite a vigorous election campaign.

Feisty campaign

Stanishev's Bulgarian Socialist Party (BSP) and the Movement for Rights and Freedoms (MRF) – a formation that mainly represents the country's ethnic Turks – had been crying "foul" almost before the game began, doubting the neutrality of the presidentially-appointed caretaker government tasked with holding elections and, in particular, predicting that the interior ministry, still headed by a "Tsvetanov insider", would exercise a baleful influence on the polls. The prosecutor's latest moves won't do much for the ministry's credibility. Add this to politicians' desperation to blame each other for the public grievances so spectacularly aired in February, and you've got a formula for a month-long slanging match.

The outcome could be complicated. One complication, admittedly, seems to be absent. February's protest movement was radical and diverse in the demands it threw up: these included not just lower power prices and the renationalisation of Bulgaria's foreign-owned power distribution companies, but also a new constitution, recallable MPs, public representation on regulatory bodies – and even, briefly and in isolated quarters, abolition of parliament and/or political parties. And opinion polls in late March suggested that 14% of Bulgarians would vote for a "protest party" if there were one. As it turns out, there are six running in the elections, with the protest movement divided in terms of aims and personalities – and by very Bulgarian suspicious about what interests are behind whom. Long term, one or more of them could be important and popular radicalism could revive. Short term, it's unlikely that any will end up in the next parliament by achieving the 4% share of the vote required for entry.

So the contest is, for now, still mainly between established political forces. And, though Bulgarians don't trust opinion polls, those polls have recently – apart from one derided outlier in March that showed GERB at almost double the BSP's level of support – have been reasonably consistent. Above all, no one is heading for anything like a majority in Bulgaria's 240-seat parliament. GERB has been appreciably, though not dramatically, ahead of the BSP, with the MRF and the extreme Bulgarian nationalist Ataka certainly heading for parliament, and former EU Commissioner Meglena Kuneva's Bulgaria for its Citizens (BfC) probably doing so.

Thus, a poll conducted by the Mediana agency April 4-9 showed GERB at 26.4% of respondents, BSP at 23.7%, Ataka at 6.2%, MRF at 5.8% and CfB at 4.5%. That would give GERB around 95 MPs in Bulgaria's 240-seat parliament, the BSP 85, with Ataka and MRF above 20 seats apiece and Kuneva's party with around 16.

With the 4% barrier applying to votes cast, rather than to the entire electorate, election of a sixth force would seem not to be inconceivable: according to Mediana, Democrats for a Strong Bulgaria (DSB) – the party of late-1990s rightist premier Ivan Kostov – is at 2.4% of respondents. Failure to unite with other factions of the "conventional right" limits Kostov's chances, however, while the sort of free market policies Kostov has traditionally backed aren't necessarily big vote winners in the current populist climate.

All this needs to be qualified by reference to statistical margins of error and to the fact that a month is a very long time in politics. For instance, GERB – so Mediana's Kolyo Kolev told the press – had surged five percentage points in the previous month, apparently benefitting from a strategy of concentrating its rhetoric on the idea that it was the only party that could stop "former communists" from getting back into power, a reference to Stanishev's BSP. One might add that, now out of government – in what some saw as an irresponsible resignation – GERB doesn't have to deal with the considerable flak being suffered by the caretaker cabinet over a crisis situation in Bulgarian energy, which has cut the country's coal production drastically and angered its miners. But it's doubtful whether anti-communism alone will get GERB through the election campaign, while there's plenty of ammunition for the opposition to use about electricity – and indeed phone-tapping. Meanwhile, Borisov is less of an asset than he used to be: his earthy charisma has been eroded by years in government and over-exposure.

As to the BSP, it might well gain from the campaign. A somewhat hesitant figure as prime minister between 2005 and 2009, Stanishev has developed politically in opposition into a formidable predator with a keen instinct for his opponent's jugular. Last year, he decisively saw off an intra-party challenge from Georgi Parvanov, whose term as state president had ended early in 2012. More recently he's improved the party's image – and electoral chances – by excluding some senior BSP figures from the party's election lists. It remains to be seen what further revelations he has to embarrass Borisov and friends in the coming weeks. And, "former communists" or not, the BSP's left-leaning policies – including, ironically, abolition of a flat-rate income tax that the party itself introduced in government – will give it some credibility in the wake of the protests. At the same time, Stanishev's choice for prime minister is, not himself, but former finance minister Plamen Oresharski, an ostensibly non-party figure with a right-of-centre background and a (possibly deserved) reputation for fiscal probity. Which both reassures financially and absolves Stanishev from charges of being power-hungry.

Outside of the main two parties, the core ethnic Turkish support means the MRF isn't likely to suffer serious losses. And the party should benefit, perhaps electorally and certainly in terms of possible alliances, from the apparently genuine departure of its widely distrusted long-term leader Ahmed Dogan earlier this year.

Looking set for electoral extinction at the beginning of this year, Ataka's riding high – and might ride still higher – on the populist mood that underlay February's protests: its mercurial leader Volen Siderov has developed a fine line in rhetoric against "colonial slavery" and domination by foreign firms, and seems to have no compunction about disco re-nationalisations that most other politicians would privately recognise as a can of worms.

As to Kuneva's BfC, don't count on it. Ructions between the central leadership and local chapters over election lists have already led to mass defections in several towns, and probably betoken quite a potential for implosion. Voters may draw conclusions before the election.

Coalition confusion

The parliamentary arithmetic could be complicated – and will be much influenced by turnout and precisely who clears that 4% barrier. It's pretty clear that no party will be able to form a government by itself. However, coalitions might be hard to form.

Asked last week about possible coalitions, Tsvetanov replied that GERB would "never" form one with the BSP, Ataka, or the MRF. Further questioned about BfC, he replied: "Let's wait and see who will win seats in parliament." Kuneva has recently ruled out any coalitions – though she's not been widely believed. Meanwhile, MRF leader Lyutfi Mestan has urged politicians to get real: coalitions are inevitable, he's argued.

The smart money at present is probably on a BSP-MRF-BfC coalition, but it's hardly a foregone conclusion. A parliament in which Ataka holds the balance isn't to be ruled out. Nor is prolonged haggling, ending in some kind of national unity government – or new elections. Meanwhile, there's a medium-term question of whether the protest movement could be revived.

The spectacle of politicians failing to reach agreement might do it. So might next winter.