Striker Lucas Akins says Burton need spirit, not slickness to seal automatic promotion for a second successive year.
Burton's draw with League One leaders Wigan on Tuesday left them second.
With three matches left, Albion are three points ahead of third-placed Walsall, who have a game in hand.
"Sometimes it's not quality or technical ability that you need, but the heart and desire to get over the line. It's up to us now to go on and finish the job," Akins said.
"We have a fantastic opportunity. We need to show character and mental strength."
Burton, who won promotion to England's third tier for the first time last season as League Two champions, have taken just four points from a possible 18 from their previous six games to slip from the summit.
Akins said the challenge of facing relegation-threatened Colchester, who need to win on Saturday to avoid the drop, will help bring the best out of Burton.
"It's better for us to play teams like that, rather than teams with nothing to play for and who play with no fear whatsoever," Akins told BBC Radio Derby.
"There are the games where you need to be patient, we need to stick together. "