Pahor stands for the SD, but his candidacy is also backed by 4,453 voter signatures, head of his campaign headquarters Nataša Kovač said as she registered the candidate. Pahor himself was not present at the event.

According to Kovač, the reason for his absence is the special type of campaign pursued by Pahor in which he is spending a working day at different working stations across the country.

He has so far worked as a road maintenance and a factory worker, hairdresser, radio host, journalist, farmer, among other things. Today he is visiting the Krško N-plant as a member of a team of nuclear energy experts.

Asked about the the campaign's financing, Kovač said the goal was to spend as little money as possible and only as much as could be raised through donations, which are being solicited from companies.

The SD will not contribute financial funds for the campaign, having financial difficulties itself, but it has provided the staff, network and activists who are doing the job voluntarily, Kovač said.

Although candidates have time until midnight on 17 October to register for the election it appears that this time voters will have the lowest ever number of candidates to choose from.

A total of thirteen people have announced their intention to stand, but only three have so far met the conditions to file their bid.

Incumbent President Danilo Türk was the first to file 13,000 voter signatures at the end of August, followed by Milan Zver on Wednesday in a bid backed by the ruling Democrats (SDS) and New Slovenia (NSi).

To stand with the support of voters, candidates need to collect at least 5,000 signatures.

Alternatively, candidates may also be put forward by ten MPs or by political parties, in which case the candidacy needs to be backed by at least three MPs or 3,000 voters.

Campaigning for the election will formally start on Friday.