Angel Martinez scored his first-ever goal for the Seasiders to secure a 1-0 win over the Elland Road outfit as Blackpool look for immediate promotion back to the Premier League via the play-offs.
Holloway said: "I'm absolutely delighted, I'm on top of the world.
"That was as tough a game as you'll ever have, as tense a game as you'll ever have and I thought Leeds came here and made it really difficult. Yet we managed to attack with lots of excitement - some of my young lads running with it and Lua (Lomana LuaLua) twisting and turning.
"We showed a lot of belief when we needed to. I'm very, very pleased with everybody concerned."
Blackpool secured promotion to the Premier League in 2010 after beating Cardiff City 3-2 in the play-off final at Wembley.