The Japanese meteorological agency confirmed there was no tsunami risk following the jolt.
It comes after a powerful 6.6-magnitude quake in September rocked Hokkaido.
There is no danger of a tsunami from the quake.
Power demand on Hokkaido in winter is typically more than a third higher than in the warmer months before the quake.
Japan's trade minister Hiroshige Seko calls on the island's businesses and 5.3 million residents to use about 20% less energy to prevent further blackouts.
Abe toured the city and commercial hub of Sapporo, where Thursday's 6.6-magnitude jolt has left houses tilted and roads cracked.
The majority of the dead are from the small rural town of Atsuma, where a cluster of dwellings were wrecked.
Soldiers in fatigues and orange-clad rescue workers searched for survivors, picking through debris on huge mounds of earth near the epicentre in Atsuma in southern Hokkaido.
Gempa bumi kuat bermagnitud 6.7 mengegar Hokkaido, utara Jepun pada awal Khamis menyebabkan tanah runtuh di kawasan pergunungan.
Aerial views showed dozens of houses destroyed at the bottom of a hill, with a rescue helicopter winching a resident to safety.
Japan began on Wednesday to clean up after typhoon Jebi killed 11 people, injured hundreds and stranded thousands at Kansai Airport.
3 million homes lost power after the quake damaged a major thermal plant supplying the region.
Officials warns of the risk of further quakes.
Masazo Nonaka took the title from the recently-deceased Francisco Núñez Olivera.
The construction of a nuclear plant in Ōma had been opposed by many people.
Bapa mangsa mengakui "bertindak melampau" dengan meninggalkan anaknya di tepi jalan, tetapi menegaskan ia adalah demi kebaikan kanak-kanak itu.