[2] The first round was planned for December 2024 but on 15 March 2024 incumbent president Zoran Milanović announced he would run as a candidate of the Social Democratic Party of Croatia (SDP) for the position of prime minister.

[5] The leadup to the election was marred by several controversies, including the November arrest and subsequent dismissal of Minister of Health Vili Beroš on various corruption-related charges.

[6][7] This caused a standoff between Croatian law enforcement agency USKOK and the European Public Prosecutor's Office, one of whose investigations was blown by the arrest.

[6][8] Another controversy happened around the same time when Milanović vetoed the government's proposal to involve Croatia in a NATO operation training Ukrainian soldiers.

The timeframe for collecting the said number of signatures is set at twelve days, and after the expiry of this period potential candidates must submit them to the State Electoral Commission for verification.

The incumbent, Zoran Milanović, ran on an anti-corruption campaign, opposing social inequality and growing inflation, which he attributed to policies of the HDZ government.

He promised to "offer special attention to the rights" of Croats in Bosnia and Herzegovina,[73] and prevent Serbia from joining the EU unless it provided Croatia with access to archives containing information about mass graves from the Croatian War of Independence (1991–1995).

[75] Milanović attended only a single debate, on 23 December, during the first round of the elections,[76] but his ratings remained high due to the popularity of his presidency.

[77][better source needed] On 7 December a group of Croatian veterans from Imotski held a peaceful protest at the Vinjani Donji–Gorica border crossing against what they claimed was a "media blockade of candidate Tomislav Jonjić".

[81] On the same day, the Jutarnji list newspaper prematurely ended an online election poll after receiving 25,000 votes tipping the scale to Primorac in a short timespan from US-based internet addresses.