a 50% of votes from at least 33.3% of the constituency win election outright in a single-member constituency. If no candidate received the required level of support, a second round was scheduled two weeks later, in which all candidates who received at least 7% of votes in the first round could take part. The candidate who received the most votes—not necessarily an absolute majority—win the constituency. The two-round system was adopted despite the objection of opposition groups, who demanded proportional representation. The first round of the elections was scheduled for 22–23 April, and the second round for 6–7 May. Political parties The first opposition groups in Croatia were set up as civic associations in 1989. The first among them was the Croatian Social Liberal Union (—HSLS), which was founded on 20 May 1989 and was later renamed the Croatian Social Liberal Party. The Croatian Democratic Union (—HDZ), which would later become the main opposition to the SKH, was founded on 17 June 1989 but was registered on 25 January 1990. The HDZ held its first convention on 24–25 February 1990, when Franjo Tuđman was elected its president. On 1 March 1990, the Coalition of People's Accord (—KNS) was formed as an alliance of the Croatian Christian Democratic Party (—HKDS), the Social Democratic Party of Croatia (—SDSH), the Croatian Democratic Party (—HDS), the HSLS and five independent candidates; Savka Dabčević-Kučar, Ivan Supek, Miko Tripalo, Dragutin Haramija and Srećko Bijelić, who were prominent figures of the 1971 Croatian Spring political movement. On 17 February 1990, the Serb Democratic Party was founded, but failed to spread its organization significantly beyond Knin. Generally, organizational skills of the parties varied significantly; only SKH candidates stood for election in every constituency. The HDZ did not field candidates in 82 constituencies (25 for the Council of Municipalities and 57 for the Council of Associated Labour). On 5 February, Croatian authorities registered the first seven political parties, including the SKH, HDZ, HSLS and several other members of the KNS. Eighteen political parties and many independent candidates took part in the election. 1,609 candidates ran for seats in the parliament. On 20 March, the SKH decided to change its name to League of Communists of Croatia – Party of Democratic Reform (—SKH-SDP). Campaign The election campaign took place from late March until 20 April, employing a mix of traditional devices and concepts inspired by election campaigns in the West.