James leapfrogged Milwaukee's Giannis Antetokounmpo and now leads him by more than 140,000 votes in the second vote tabulation, released by the NBA on Thursday.
Golden State's Stephen Curry leads the voting in the Western Conference, pulling ahead of teammate Kevin Durant by more than 40,000 votes.
The conference leaders are significant this season. Under a new All-Star Game format, the player who receives the most votes in each conference will serve as a captain, choosing his team from the pool of players voted in as starters and reserves.
As in previous seasons, the starters will be determined by the fan vote as well as a vote among current players and media. Fans will account for 50 percent, while all current players and a media panel will account for 25 percent each. Voting will conclude Monday.
Players will be sorted by conference and position (guards and frontcourt players), and the two top guards and three top frontcourt players will be named starters. NBA head coaches will select the reserves. The two captains will then draft a team based on the pool of players.
In the Eastern Conference, James (1,622,838), Antetokounmpo (1,480,954) and Philadelphia's Joel Embiid are currently the top three frontcourt players in the fan vote. New York's Kristaps Porzingis (640,928) is fourth. Kyrie Irving (1,370,643) and Toronto's DeMar DeRozan (537,168) are the top two guards. Philadelphia's Ben Simmons (397,942) is third.
In the Western Conference, Durant (1,326,059), New Orleans' Anthony Davis (664,687) and Golden State's Draymond Green (616,730) are the top three frontcourt players. New Orleans' DeMarcus Cousins (587,835) is fourth.
Curry (1,369,658) and Houston's James Harden (978,540) are the top two guards. Oklahoma City's Russell Westbrook (791,332) is third.
The starters and captains will be revealed Jan. 18, and the reserves will be announced Jan. 23. Full team rosters will be announced Jan. 25. The All-Star Game will be Feb. 18 in Los Angeles.