Gyeonggi Province Gov. Lee Jae-myung clinched another victory in the ruling Democratic Party's(DP) presidential primary, cementing his lead. 

Lee earned 51-point-09 percent of 496-thousand-672 votes in the first of three rounds of electoral college votes held on Sunday at Oak Valley Resort in Wonju, Gangwon Province.

Former DP chair Lee Nak-yon finished second with 31-point-45 percent. It marks the first time that Lee secured over 30 percent of votes in the primary sessions that started last Saturday. 

The governor is far ahead of Lee, securing an accumulated 51-point-41 percent from the electoral college and four regional primaries over two weekends. Lee has garnered 31-point-08 percent of the votes so far. 

In the electoral college on Sunday, former Justice Minister Choo Mi-ae came in third with eleven-point-67 percent while former Prime Minister Chung Sye-kyun finished fourth with four-point-03 percent.