The Millers made it nine games without defeat after goals from Michael Smith and Joe Newell saw off a Bantams side who are struggling of late.
They moved into the final play-off spot and are looking like a good bet to maintain that challenge, not that Warne is looking too far ahead.
“I am not overly giddy about it, there is still 17 games to go. The lads are in fine fettle, but there are some real tests ahead,” Warne said.
“It’s great to win back-to-back games but it wasn’t long ago that we couldn’t win a game, so I know how quickly football can change.
“Potentially we can win a lot more games to get us in a good position at the end of the league. I am pleased with where we are but I’m not getting carried away.
“We are pleased with what they are doing and they are well aware that potentially they could be a really good team.
” The Millers took the lead in the 22nd minute when Smith headed home his first goal for the club on his first start, though it was an even contest, with Bradford spurning chances to level.
The second half was one-way traffic, though, and Newell’s cool 57th-minute finish ensured the points stayed in South Yorkshire.
Warne added: “I thought second half we were really good and I think we deserved the win. “We were a threat and I thought we could have got more goals.”
For Bradford it was a fourth defeat on the spin in all competitions and the fourth time they have been to Rotherham’s New York Stadium and left without scoring.
Boss Stuart McCall has seen his side slip out of potential automatic promotion contention and knows his side were no match for the Millers.
“It was a complete lack of performance,” he said.
“There were no excuses, no pointing the finger at anyone else, we had a good enough team out tonight to do far better.
“They were strong and physical and we couldn’t cope. We knew set-plays would be crucial and we gave a silly free-kick away.
“We’ve had a good 18 months here and this is the first test for me and the players. But the only way to put that right is out on the pitch.
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