Town have sold more than 25,000 tickets for Saturday’s home game against Cambridge United.
The Blues go into the match top of the division on goal difference from Portsmouth and unbeaten.
The U’s have also made a strong start to the campaign and sit in fifth in the table but having been beaten twice and drawn once in their three away games up to now, while winning all four of their home matches.
Town will be looking to beat Cambridge in the league for the first time in their history with the U’s having won two - including last season’s Portman Road fixture - and drawn two of the past meetings.
The Blues will be hoping that sales over the next few days will take the total of seats sold above the 26,688, the highest crowd this season which watched the 1-1 opening-day draw with Bolton Wanderers.
Tuesday's game is the first of two at home in the week with Bristol Rovers at Portman Road next Tuesday.