Brown has been sortlisted for the managerial honour for November while defender Luke Prosser has been recognised for his efforts on the pitch last month.
Having progressed in the FA Cup first round, the Shrimpers came close to recording a fifth successive league victory in November on Saturday as Cheltenham converted an injury-time penalty to rescue a draw.
And boss Brown believes that although he and Prosser are grabbing the headlines, all of the playing and backroom staff at the Essex club are responsible for the success.
He said: "It has been a very good month for us and it would have been absolutely fantastic had we held on for those last 20 seconds against Cheltenham.
"It's down to all the hard work, not just from the players but everyone in the backroom team from Dave Penney to Graham Coughlan and Ben Clarkson the physio - everyone has played their part in a very successful month.
"Luke has been immense and funnily enough it has happened ever since he started wearing that headband. It has been a bit of a joke with the lads but he wears it for protection for a cut above his eye. It also reminds him, though, that he's a centre-half who needs to head it and be dominant.
"He is doing the basics well, he got the winning goal against York and he's been top drawer in the last six games."
Brown will compete against Burton boss Gary Rowett, Accrington manager James Beattie and Bristol Rovers' John Ward.
Prosser, meanwhile, is up against Chesterfield midfielder Ollie Banks, Dagenham forward Zavon Hines and Fleetwood midfielder Steven Schumacher. The winners will be announced on Friday.
- Sports & Recreation
- Luke Prosser