The Congress is composed of a Senate and a Chamber of Deputies. Consecutive re-election is prohibited. Senators are elected to 6-year terms, and deputies serve 3-year terms. The Senate's 128 seats are filled by a mixture of direct-election and proportional representation. In the lower chamber, 300 deputies are directly elected to represent single-member districts, and 200 are selected by a modified form of proportional representation from five electoral regions. The 200 proportional representation seats were created to help smaller parties gain access to the Chamber. | The Congress is composed of a Senate and a Chamber of Deputies. Consecutive re-election is prohibited. Senators are elected to 6-year terms, and deputies serve 3-year terms. The Senate's 128 seats are filled by a mixture of direct-election and proportional representation. In the lower chamber, 300 deputies are directly elected to represent single-member districts, and 200 are selected by a modified form of proportional representation from five electoral regions. The 200 proportional representation seats were created to help smaller parties gain access to the Chamber. |