MANILA - If you've been seeing more and more national candidates lately, you're probably in one of those vote-rich provinces that could decide their fate in the May elections.
Despite huge spending on TV advertisements, those running for national positions acknowledge the importance of campaigning in the flesh and being able to actually shake the hands of potential voters.
"You cannot rely solely on television ads for a campaign," said Lito Banayo, a veteran campaign strategist who is now helping the presidential candidacy of Davao City Mayor Rodrigo Duterte.
"You have to cover as much ground as possible. You have to be seen. (People) have to listen to you."
This "ground war" is significant if a candidate hopes to secure votes from another contender's known political bailiwick, while consolidating support from his own stronghold, said political analyst Julio Teehankee, dean of De La Salle University's College of Liberal Arts.
But waging this political war requires a significant amount of physical effort, not to mention, huge resources.
More than half of the estimated 54 million registered voters for the May elections are located in Luzon, while the rest are nearly divided equally between Mindanao (23 percent) and the Visayas (21 percent).
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Banayo, who has campaigned for at least three presidential candidates, acknowledged the difficulty for a contender to visit all 81 provinces in the country.
Given the three-month campaign period, which begins on February 9, he said to go around 75 percent of these provinces would be a good target for a national candidate.
Candidates usually cover at least two provinces daily, spending 3 to 4 hours in each sortie, he said.
Schedule is planned in a way that they would cover as much ground as possible, with motorcades, press conferences, and rallies.
Banayo said evenings were often spent meeting with local leaders.
Candidates usually make their presence felt in provinces like Cebu, which has the most number of registered voters at around 2.7 million.
"Let's be honest. You don't normally go to Batanes, not for any reason, but because of remoteness and the small population size," Banayo told ABS-CBN News.
Batanes has the fewest number of registered voters at only 11,006, based on the Commission on Elections' (Comelec) records.
Behind Cebu with the most number of voters are Cavite, Pangasinan, Laguna, Negros Occidental, Bulacan, Batangas, Rizal, Iloilo, and Nueva Ecija.
They account for 16.9 million voters, which is 878,729 more than the number of registered voters in the 2013 elections.
Filipinos working abroad also account for more than 1.3 million registered voters.
Vice President Jejomar Binay's latest visit was to two cities in the United Arab Emirates, which have close to 200,000 voters.
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Senator Grace Poe, who is running as an independent presidential candidate, has visited Pangasinan (1.7 million voters) at least twice, and has frequented Cebu and the Davao region (2.6 million voters) as well.
But her spokesman, Valenzuela Mayor Rex Gatchalian, said the visits were not all about the May elections. He noted that Poe had been getting invitations from Pangasinan, home province of her late adoptive father, Fernando Poe Jr.
"We don't just look at the dynamics of how many voters there are," Gatchalian said. "We have to visit as many provinces, as many cities, as many municipalities and try to explain to the people why we're running."
Teehankee recalled how face-to-face campaign helped then Makati Mayor Jejomar Binay score an upset in the 2010 vice presidential elections.
"The key to [his] success was really back-to-basic, ground, grassroots campaigning," Teehankee said. "It's as if he treated the entire country as a larger version of Makati."
As mayor, Binay was known to diligently visit wakes and household, an effort that showed dividends come elections.
Now that Binay is running for president, Teehankee noted how "he has gone around the country several times, even in nooks and crannies that no [other] candidates have gone before."
Navotas Rep. Toby Tiangco, president of Binay's United Nationalist Alliance (UNA), said Binay had probably gone around the country more than any other presidential candidate.
"The difference is that while others are probably doing it because it's important for their campaign," Tiangco said, "this is who he is. He's used to this. He's comfortable doing it."
Supporters of vice presidential candidate Leni Robredo are also banking on her grassroots campaign.
Senator Bam Aquino, Robredo's campaign manager, cited a recent survey supposedly suggesting she had strong chances of winning in areas she had already visited.
"It appears that if Leni is able to go to a place and people get to know her, the 'conversion' is immediate," Aquino said, referring to how people's familiarity with a candidate translates to actual votes.
Campaign strategists agree that much of the election battle is waged on air and on social media.
But at the end of the day, ground campaign allows voters to see if the candidates they meet in the flesh are consistent with the images they see in well-funded media ads.