The Institutional Social Democratic Bloc is a left-wing and social democratic political party

Political party

A political party is a political organization that typically seeks to influence government policy, usually by nominating their own candidates and trying to seat them in political office. Parties participate in electoral campaigns, educational outreach or protest actions...

 of the Dominican Republic

Dominican Republic

The Dominican Republic is a nation on the island of La Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. The western third of the island is occupied by the nation of Haiti, making Hispaniola one of two Caribbean islands that are shared by two countries...

. It first contested national elections in 1994

Dominican Republic general election, 1994

General elections were held in the Dominican Republic on 16 May 1994. Joaquín Balaguer of the Social Christian Reformist Party won the presidential election, whilst the Dominican Revolutionary Party-led alliance won the Congressional elections. Voter turnout was 87.6%.Despite reforms after the 1990...

 when it was part of a Dominican Revolutionary Party

Dominican Revolutionary Party

The Dominican Revolutionary Party is one of the main political parties of the Dominican Republic. It has a moderate centrist position, social democratic in name. The party's distinctive color is white....

-led alliance that won the Congressional elections. It was again part of the winning PRD bloc in the 1998 elections

Dominican Republic parliamentary election, 1998

Parliamentary elections were held in the Dominican Republic on 16 May 1998. The result was a victory for the opposition Dominican Revolutionary Party-led alliance, which won 83 of the 149 seats in the House of Representatives. Voter turnout was 52.9%....

, before switching its allegiance to the Dominican Liberation Party

Dominican Liberation Party

The Dominican Liberation Party is one of the main political parties of the Dominican Republic, and has a centrist position.The party has been elected into office thrice now with Leonel Fernández as President of the Dominican Republic in the 1996, 2004 and 2008 elections, though losing in 2000...

 for the 2002 elections

Dominican Republic parliamentary election, 2002

Parliamentary elections were held in the Dominican Republic on 16 May 2002. The result was a victory for the opposition Dominican Revolutionary Party-led alliance, which won 73 of the 150 seats in the House of Representatives. Voter turnout was 51.0%....

. In the 2006 elections

Dominican Republic parliamentary election, 2006

Parliamentary elections were held in the Dominican Republic on 16 May 2006. They were won by the Progressive Bloc led by the Dominican Liberation Party, which took 96 of the 178 seats in the Chamber of Deputies and 22 of the 32 Senate seats....

 it was part of the victorious Progressive Bloc

Progressive Bloc

The Progressive Bloc is an electoral alliance in the Dominican Republic. The alliance is led by the Dominican Liberation Party and gained an absolute majority in the 16 May 2006 legislative election.-Electoral strength:...

.