“Leni Robredo: The woman leading the Philippines' 'pink revolution'” https://www.bbc.com/news/world-asia-61318519
Ms Robredo, 57, a former human rights lawyer and economist, is the main opponent to Mr Marcos Jr, the frontrunner in the 9 May election.
She entered politics after her husband, a former cabinet minister, died in a plane crash in 2012.
In 2013, she successfully ran to become a representative for Camarines Sur in Congress. As a politician, Ms Robredo gained a reputation for being hands-on with voters' problems, visiting low-income areas and remote provinces, speaking directly to the people.
When the country was hit by natural disasters she co-ordinated additional aid and relief efforts. As vice-president, Ms Robredo also took a prominent role in distributing PPE and testing kits during the Covid-19 pandemic. She criticised current President Rodrigo Duterte for lacking decisive leadership during the crisis, at one point asking for blanket authority to tackle Covid-19.
"There's so much that should have been done that's not being attended to, and it's frustrating because we've been asking for these things since last year," she told the Rappler news website in September 2021.
Some have compared her political career to that of former president Corazon Aquino, who rose to power after her senator husband and pro-democracy icon Benigno "Ninoy" Aquino Jr was assassinated. His murder spurred massive protests that ousted Ferdinand Marcos.
Ms Robredo took part in those protests and even used the colour yellow, synonymous with the People Power movement, running as a Liberal Party candidate in her 2016 campaign for vice-president. She beat her opponent, who happened to be Mr Marcos Jr, after trailing him in the polls. He contested the result, bringing about a lengthy court case which was eventually thrown out by the Supreme Court.
But this time Ms Robredo is up against not one but two of the most powerful political families in the Philippines - running alongside Mr Marcos Jr for vice-president is Sara Duterte, the daughter of the current president. Together, they hold sway in both the north and south of the country.
In an attempt to unite the opposition, Ms Robredo is running as an independent, not for the Liberal Party which she still chairs - and which has long been associated with the colour yellow. That may explain her decision to switch to pink when she launched her candidacy last October*4.
It's become her campaign colour, worn by supporters who include many celebrities and leading figures in the country.
Although she served alongside Mr Duterte, Ms Robredo has an acrimonious history with him. As vice-president, she has been a fierce critic of his brutal war on drugs that has left thousands dead.
Incensed by the criticism, Mr Duterte challenged her to lead the contentious campaign in 2019. She vowed to stop the killing of innocent people and hold officials accountable.
"The president knows what my position is on the drug war. If he thinks that in my accepting this offer I will become silent, he is mistaken," she said.
But she was fired from the job 19 days later - lack of trust was cited as one of the reasons*5.
Those who back Ms Robredo are hoping their "pink revolution" will steer the country back to family values and the rule of law.
But her campaign, fuelled by young volunteers, has had to battle misinformation and a years-long concerted effort to rewrite history.
Social media posts across platforms have sought to present the Marcos presidency as a "golden age", and YouTube and TikTok videos on Mr Marcos Jr have captured the attention of young voters who have no memory of living under martial law imposed by his father.
The platform has also been deployed to discredit Ms Robredo, including sexist and misogynistic remarks and allegations of affairs and a sex tape involving one of her daughters. Ms Robredo denied all the accusations.
Howard Johnson & Virma Simonette “Bongbong Marcos: The man attempting to revive a corrupt political dynasty” https://www.bbc.com/news/world-asia-61212659
*1:See also https://sumita-m.hatenadiary.com/entry/20110203/1296712681 https://sumita-m.hatenadiary.com/entry/20130130/1359519625 https://sumita-m.hatenadiary.com/entry/2019/03/24/015503
*2:See also https://sumita-m.hatenadiary.com/entry/20091203/1259847415 https://sumita-m.hatenadiary.com/entry/20140927/1411833989 https://sumita-m.hatenadiary.com/entry/20170321/1490068443
*4:See Mara Cepeda “Yellow out, pink is in: Robredo runs for president as an independent” https://www.rappler.com/nation/elections/video-robredo-runs-president-as-independent-2022/
*5:See “Philippines: President Duterte's fierce rival stripped of 'drug czar' post” https://www.bbc.com/news/world-asia-50537574