Religion played an important role in the political life of the Netherlands. During World War II, strenuous efforts were made to reduce this role, but denominational parties continued to exercise considerable influence. However, since the mid-1960s the general trend has been toward the polarization of politics into conservative and progressive parties, and denominational parties have lost voter support.
The religious political party with the largest membership throughout the postwar period was the Catholic People's Party (Katholieke Volkspartij—KVP), which favored democratic government and a middle-of-the-road social policy. It began to lose votes in the 1960s and the KVP joined the Anti-Revolutionary Party (Anti-Revolutionaire Partij—ARP) and the right-wing Christian Historical Union (Christelijk-Historische Unie—CHU) to form the Christian Democratic Appeal (CDA) to contest the 1977 elections. When this alliance did not yield a real improvement in the electoral position of the confessional parties, they merged to form CDA, which governed the Netherlands in the 1980s under the leadership of Ruud Lubbers. The Labor party (Partij van de Arbeid—PvdA) vied for political leadership with the KVP in the first decades of the postwar period, polling about the same number of votes in national elections until 1972, when the PvdA won a plurality of nearly 25% of the total vote and emerged as the dominant member of a centrist coalition government. The Labor Party, while calling itself socialist, has appealed mainly to national interests rather than to socialist ones, although it does favor redistribution and solidarity. Since 1986, it has pursued de-radicalization and has moved to the political center. The conservative People's Party for Freedom and Democracy (Volkspartij voor Vrijheid en Democratie—VVD) advocates free enterprise, separation of church and state, and individual liberties.
Since 1965, discontent with the major political parties and erosion of party discipline have led to the establishment of change-oriented parties like Democrats 66 (Democraten 66— D66), which pushes for greater democratic accountability, political transparency, and involvement of the citizen in the policy process. Smaller parties include the left-wing Green Left (Groen Links—GL), which is the product of a merger of socialist and ecology parties in 1991, and three small social conservative Calvinist parties: the Political Reformed Party (Staatkundig Gereformeerde Partij—SGP), the Reformed Political League (Gereformeerd Politiek Verbond—GPV), and the Reformatorian Political Federation (Reformatorische Politieke Federation— RPF). Combined, they usually garner around 5% of the vote and 8 seats in parliament. Finally, the Socialist party (Socialistische Partij—SP) is a radical left party.
As no single party commands a majority in the States-General, the governing cabinet is a coalition of various party representatives, according to their numerical strength. In 1994, for the first time in 80 years, a coalition emerged which did not include a confessional party. The Labor party won a plurality of votes in spite of an absolute loss of votes. Its closest ally, D66, absolutely refused to join a coalition government with the Christian Democrats. In 1994, the first "purple" cabinet emerged, led by Wim Kok of the Labor party, and composed of D66 and the VVD. In 1998 the government fell after D66 failed to push through parliament a bill to make more use of referendums. A month later, in June 1998, voters brought back the purple coalition and Kok led another government of VVD, D66, and PvdA.
Willem Kok initially let it be known in various interviews that he would stand again in the 2002 election, greatly increasing the likelihood of another four years of Labor Party leadership. However, in April 2002, Kok's government resigned following an official report criticizing its role in the 1995 Srebrenica massacre in the former Yugoslavia, when some 100 lightly armed Dutch peacekeepers failed to stop Bosnian Serb forces from murdering around 7,000 Muslims.
Elections were held on 15 May 2002, and resulted in a victory for the Christian Democrats. A surprise showing was made by the List Pim Fortuyn (LPF); a political party formed just a month earlier by the anti-immigrant politician Pim Fortuyn. Fortuyn was assassinated just prior to the election, but his party came in second. Labor, the VVD, and D66 all suffered losses. Christian Democratic leader Jan Peter Balkenende became prime minister; however, his government collapsed in October 2002, and new elections were held on 22 January 2003.
Following the January 2003 elections, the 150 seats in the Second Chamber of the Legislature were distributed as follows: CDA, 28.6% (44 seats); PvdA, 27.3% (42 seats); VVD, 17.9% (28 seats); SP, 6.3% (9 seats); LPF, 5.7% (8 seats); GL, 5.1% (8 seats); D66, 4.1% (6 seats); the Christian Union (CU), 2.1% (3 seats); and the conservative Calvinist party Political Reformed Party (SGP), 1.6% (2 seats). The PvdA scored an increase of 19 seats over the May 2002 elections, and the LPF suffered a loss of 18 seats. Balkenende formed a coalition government composed of the CDA, VVD, and D66.