"At half time on Boxing Day we were actually in the relegation zone and, since that time, we have scored enough points to be in the play-offs," chairman Bates told Leeds' official website.
"That augurs well for next season. I have great confidence in Kevin Blackwell, he took over as manager and had very little to play with and the job he has done this season has been outstanding.
"He deserves the opportunity to start next season with a level playing field. Kevin Blackwell has my unqualified support, I told the players that on the first home game since I took over and that remains unchanged.
"I also have to thank the backroom staff, not the guys at Thorp Arch who know what I think of them anyway, but the many staff at Elland Road who do not earn a lot of money but love the club and have worked their guts out to keep the club going against the odds."