In district elections, 219 single-member constituencies elect one member of the House of Representatives. The candidate with the highest number of votes wins that district's seat. In the party-list election, the parties with at least 2% of the national vote were elected, and 21 representatives were elected However, later in 2007 the Supreme Court ruled in Banat vs. COMELEC that the 2% quota was unconstitutional, and that the sectoral representatives should comprise exactly 20% of the House. This led to the increase in the number of sectoral representatives to 51.
The Genuine Opposition (GO) targeted to win at least 80 seats to be able to impeach President Gloria Macapagal-Arroyo; however the administration's TEAM Unity prevented GO in winning several of those seats by fielding in strong candidates against GO in those districts.
The administration's two main parties, Lakas-CMD and Kabalikat ng Malayang Pilipino (KAMPI), was seen to win majority of the seats, with most contests contested by the two parties. This inevitably produced a split in the administration ranks on who would be their candidate for Speaker in the impending victory. However, the two parties were united in supporting President Arroyo and were able to prevent any impeachment proceeding against her or her allies from reaching the Senate.
Result of the Philippine House of Representatives party-list election. Proportion of votes (inner ring) as compared to proportion of seats (according to VFP vs. COMELEC, middle ring; final allocation according to BANAT vs. COMELEC, outer ring) of the political parties. Parties that did not win any seat are represented by a gray pie slice.
Party-list representatives are allocated 20% of the seats in the House; however, due to the 2% threshold and the 3-seat cap rule, the 20% requirement was not met. On the BANAT vs. COMELEC decision of the Supreme Court, it declared the 2% threshold unconstitutional; instead it mandated that parties surpassing the 2% threshold automatically having seats, then allocating one seat for every party with less than 2% of the vote until the 20% allocation was met. With the formula used, this meant that the party with the highest amount of votes usually gets three seats, the other parties with 2% or more of the vote winning two seats, and parties with less than 2% of the vote getting one seat.