Real life content incoming
The 1994 Hungarian parliamentary election was the second held after the transition to democracy. Like every former Eastern Bloc nation, the first term of democratic governance was transformative but difficult. In 1990, the conservative Hungarian Democratic Forum (MDF) came to power with a slim plurality of 24% of votes cast, but a sizable 42% of seats. It formed a coalition with likeminded right-wing parties and set about transitioning Hungary to a market economy. The immediate effects were not ideal: unemployment, inequality, inflation, and crime all grew dramatically. Prime Minister Josef Antall struggled to keep his government in line. One of his coalition partners withdrew partway through the term after suffering a huge internal split, and the MDF itself suffered a small rupture when a dozen MPs left to form the far-right Life and Justice Party. Antall clashed with the nation's President, who was a member of the opposition SZDSZ, and responded poorly to strikes and protests.
Antall had been diagnosed with lymphoma shortly after entering office, and his illness worsened in the following years. He died in office on 12 December 1993, and was succeeded by his Interior Minister, Peter Boross. Boross himself faced internal opposition and only narrowly won the confidence of his party to remain in office. Ultimately, with the government's popularity sinking and a new election coming up, the MDF appeared likely to be swept from office.
The expected result was a victory for the opposition Alliance of Free Democrats (SZDSZ), a social liberal party who had spearheaded the pro-democracy movement in the late 80s. They had placed a narrow second to the MDF in 1990, and appeared well-placed to win the coming election. However, things didn't quite turn out that way.
Hungarians went to the polls on 8 May 1994, and a startling picture started to form as the results came in. The Hungarian Socialist Party (MSZP), the moderate successor of the ruling party of the Hungarian People's Republic, looked set to win. The party had tripled its vote share from 11% to 33%. Bewilderingly, the SZDSZ had in fact suffered a decline compared to 1990. Although 175 of the 176 single-member constituencies went to runoffs, the MSZP was well-placed in almost all of them. Turnout in the runoffs three weeks later was 55%, up ten percentage points compared to four years earlier, and the MSZP won a resounding victory - 45% of the vote and 149 seats, for a final tally of 209.
Not only had they claimed first place, they had won a clear majority in the National Assembly. It was an alarming result to many both in and outside Hungary - a post-communist party had returned to power just four years after the collapse of Iron Curtain. MSZP leader Gyula Horn, aware of his position, was keen to assuage fears. Although he had more than enough numbers to govern alone, he invited the SZDSZ to form a coalition government. Indeed, far from the return to socialism which many feared (and some desired), the new government went on to introduce the Bokros package - a "shock therapy" austerity programme so harsh that even the conservative opposition were outraged.
Needless to say, this was not what most of the MSZP's newfound voters had wanted, and the government became deeply unpopular. They lost to Viktor Orban's Fidesz in the next election, but only suffered a slight decline in support compared to 1994. The MSZP had successfully established themselves as a major party of Hungarian politics in record time. They came to government again in 2002, and remained until Orban's landslide victory in 2010.
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On the electoral system: from 1990 to 2010, Hungary used a modified form of the mixed-member majoritarian system. 176 of the 386 seats in the National Assembly were elected from single-member constituencies using the two-round system. It was a little more complicated than a simple runoff, though: if no candidate won 50%+1 votes in the first round, the top three candidates advanced to the second round, as did any other candidates winning more than 15% of votes. Additionally, if turnout was below 50% in any constituency, its first round result (including for the party list vote) was invalidated and the election was rerun during the runoffs, using first-past-the-post to ensure a winner. (However, if turnout in the runoff was below 25%, the seat would be declared vacant. They were really worried about this I guess.)
The remaining 210 seats were elected proportionally via two methods: 146 were distributed between 20 multi-member constituencies, corresponding to Hungary's counties, and 64 were allocated to a national leveling list to ensure some degree of proportionality. A threshold of 5% of party list votes was applied for both, although this was never a practical concern in the MMCs since all except Budapest were too small for it to apply. The application of the electoral quota in the MMCs almost always left some seats unallocated; those empty seats were added to the leveling list. This meant that the total number of leveling seats varied over time (as high as 90 in in 1990, and as low as the legal minmum of 64 in 2010.)
Once all the seats had been distributed in both the SMCs and MMCs, the party's residual votes were calculated. This included any votes over the quota in the MMCs, as well as the first-round votes of any SMC candidates who hadn't been elected. The leveling seats were then distributed to the parties based on their number of residual votes.
This system was fairly good at creating proportionality in normal circumstances, though it was probably more complicated than it needed to be. However, it broke down during landslides such as 1994 and 2010, when one party won the vast majority of single-member constituencies. Its performance in 1990 was also less than ideal.
This system was replaced in 2011 under the second Orban government. Alongside the constitutional reform which reduced the National Assembly to 199 seats, a new simplified electoral law was passed. The proportion of single-member constituencies was increased (from 46% to 53%), the proportional component was unified into a single national list, and the compensatory elements were removed. The current electoral system guarantees a strong majority for a hegemonic party who is able to consistently dominate the single-member constituencies.