Mahinda Rajapaksa and Sarath Fonseka led the campaign that finally defeated the separatist Tamil Tigers that ended a quarter-century of war.
However, since the end of the war in May, the two have become bitter political rivals in what is expected to be a tight presidential race on Tuesday.
That division is likely to split the vote of the majority Sinhalese, leaving the minority Tamils to decide the outcome of the race.
Rajapaksa and Fonseka have both courted the Tamil minority, who make up about 18 per cent of the population.
Both candidates have tried to cash in politically on their popularity among the Sinhalese majority for crushing the LTTE.
Some 80,000 to 100,000 people were believed to have been killed during the fighting, as the LTTE sought an independent state for the ethnic Tamil minority in the country's north and east.
Despite the end of the war, the lives of many of the Tamils in Sri Lanka's north remain difficult.
Al Jazeera's Wayne Hay has gained rare access to refugee camps in the north, to take a look at the challenges still faced by the Tamils living there.
Source: Al Jazeera