But it was Milwaukee that jumped out to a 35-17 lead in the second quarter by dominating the boards.
Charlotte's starters were 6 of 20 from the field at one point before Jefferson started to get hot toward the end of the second quarter and helped the Bobcats trim the lead to 54-52 at the break.
The teams entered the fourth quarter tied, but Tolliver knocked down his fourth 3-pointer with 4:02 left on the clock to give Charlotte a 96-94 lead.
The Bucks would cut the lead to one with 35 seconds left before Walker hit a pull-up jumper from 13 feet with 16 seconds left. After a timeout, Middleton missed a 3-pointer, but O.J. Mayo grabbed the loose rebound and knocked down a 25-footer to send the game into overtime.
In the extra period, the Bobcats took a one-point lead late on a free throw by Jefferson.
The Bucks had a chance to take the lead but Middleton missed a jumper and Walker grabbed his ninth rebound of the game. Walker knocked down two free throws with 1.6 seconds left to push the lead to 111-108.
Milwaukee's last ditch effort fell short when Middleton's jumper at the buzzer from the right corner went in, but was ruled a two-pointer.
Replays showed his foot was on the line.
"We just have to get over the hump," Bucks coach Larry Drew said. "We're knocking at the door. We just have to get over the hump. We're putting ourselves in position. Like I told the guys, we can have good stretches and then we have breakdowns. Bad shots are just as good as a turnover. Particularly on the road. You have to be disciplined enough to get good shots."
The Bobcats had a season-high 10 3-pointers including a 4-for-4 effort by Tolliver, who took over as the starter after Jeffery Taylor tore his Achilles tendon last week.
NOTES: The Bobcats announced that Taylor had surgery to repair a torn right Achilles tendon and is expected to miss six to nine months. ... Jefferson has scored in double digits in 16 straight games for the Bobcats. ... Former North Carolina Tar Heel P.J. Hairston was on hand for the game against the Bucks watching former college teammate John Henson.