"Yes, I've seen progress from A.J.," Harbaugh said. "He's been on his assignments. He's executed well when he's been out there. He's given great effort and football rewards that effort."
Gore, who went to the University of Miami, needs 28 yards rushing against the Dolphins to reach 1,000 for the sixth time. Only the Rams' Steven Jackson has more 1,000-yard seasons (seven) among active players.
Gore also needs one touchdown to match Roger Craig and Joe Perry (50) for most in franchise history.
"Whatever it takes," Gore said. "If there's a successful play and we win, and I'm part of it, I'm good."
Harbaugh did say the coaching staff has been talking about ways to share the load at running back.
"It's part of the game plan," he said. "We have some other backs that we feel confident with."
The 49ers have won nine consecutive home games in December, second only to the New England Patriots (19). The Dolphins have won the past two meetings between the teams, the last on Dec. 14, 2008, in Miami. The Dolphins also won in San Francisco in 2004.
The 49ers last beat Miami at home in 2001.
NOTES: Dolphins OT Jonathan Martin played for Harbaugh at Stanford. ... The 49ers' defense has allowed 23 opposing drives to reach the red zone, the fewest in the NFL.