INC members are noted for bloc voting in Philippine elections, although INC has the biggest conversion turn-out, between 68 and 84 percent of its members voted for candidates endorsed by its leadership, according to comprehensive surveys conducted by ABS-CBN. This is in part due to their doctrine on unity. Some reports say that the INC can deliver 2 million members of voting age, although pollsters believe the actual figure is closer to between 1 million and 1.5 million. Others[who?] argue that the INC vote is only significant in close-run elections, noting that some INC-supported candidates lost in the election. Businessman Eduardo Cojuangco Jr. lost to Fidel Ramos in the 1992 Philippine presidential election. Michael Defensor,Ralph Recto, Vicente Sotto III in 2007 and Ruffy Biazon in 2010 were endorsed by INC but lost in the senate election. INC endorsed Rafael Nantes and Jamie Eloise Agbayani but lost in the 2010 Quezon and 2007 Pangasinan gubernatorial elections respectively.
Ever since former Philippine president Manuel L. Quezon created a lasting friendship after asking Felix Manalo for advice, the INC has been known for its strong political influence. Not all candidates in Philippine politics however embraced support from INC. Diosdado Macapagal has refused INC’s support during his runs for Vice President in 1957, and re-election for President in 1965 – in which he lost to Ferdinand Marcos. In the 1969 presidential election, INC supported Senator Sergio Osmeña Jr. earlier in the campaign but has swung behind Marcos who won the election. The INC supported Ferdinand E. Marcos until he was ousted in 1986.
In 2002, the Philippine Center for Investigative Journalism reported that INC leader, Bro. Eraño Manalo himself wanted to support Panfilo Lacson. Eraño saw that Lacson will likely succeed Estrada. This worried Arroyo during her 2001-2004 term as President. But that did not prevent President Arroyo from courting the church. The church eventually offered their support for Arroyo’s presidential campaign in the 2004 elections. Arroyo dismissed rumors that she paid off the INC to support her candidacy. In an open letter to the INC which was read in all INC chapels across the country, Mrs. Arroyo said “I would never taint their (INC) sincerity by offering money for it”. Newspaper reports say that the Philippine Congress decision to uphold the decision on September 2005 rejecting the Arroyo impeachment complaint over alleged election fraud and corruption was swayed largely by INC influence. Behn Fer. Hortaleza Jr. says otherwise and wrote an op-ed piece for The Sun·Star Pangasinan stating that Representative Joey Salceda “had wanted to pit the INC against the Catholic church by so timing the congressman’s ‘news’ with another expose on the bishops’ receiving Pagcor “sin money” for their projects.”
The support of the INC was reportedly sought out for passage of the Reproductive Health and Population Development Act of 2008. In 2008, the INC and the Catholic Church were again pitted against each other when health advocate RH Advocacy Network (RHAN) sought the support of the INC to counter the firm opposition of the Catholic Church and President Arroyo to the bill.Representative Janette Garin of the first district of Iloilo said the INC’s stand could determine if the bill gets passed in the House of Representatives. She said the opinion of the Iglesia ni Cristo is “important” in determining the fate of House Bill 5043.
On July 27, 2008 on the occasion of its 94th Anniversary lawmakers, governors, mayors, councilors and other government officials cited the meaningful role of the Iglesia ni Cristo in Filipino society. Rep. Annie Susano of Quezon City’s second district where the INC’s executive offices are located, along other government officials said that the INC continues to contribute not only to the spiritual development of the Filipino but also in shaping the country’s destiny. Susano said INC also plays a crucial role in improving the socio-economic condition of its followers and other Filipinos, at home and abroad. A year before, on the same date, President Arroyo declared July 27 of every year as “Iglesia Ni Cristo Day” to enable millions of INC followers in the Philippines to observe the occasion with fitting solemnity. President Arroyo’s proclamation was based on a resolution of the House of Representatives authored by Rep. Annie Rosa L. Susano. On July 8, 2009, Arroyo declared that July 27 of every year as “Iglesia Ni Cristo Day” making it an official national working holiday.
In 2010, Iglesia ni Cristo has declared support for Noynoy Aquino and Mar Roxas for president and vice president respectively. Aquino won the election but Roxas lost to Jejomar Binay. In 2010, Iglesia ni Cristo withdrew their support from President Noynoy Aquino.