Broad said that the run chase was one of the best that he has ever been a part of, and now instead of being all but out of the tournament England can take momentum from the victory.
"T20 is a momentum game and the innings we chased against Sri Lanka was one of the best I've ever witnessed," he told Sky Sports News. "The confidence and belief we will get from that going into our final two group games is going to be huge. It's in our hands a little bit now.
"If we had lost against Sri Lanka we were pretty much out of the World Cup. With that sort of pressure, it's exciting to see players come through that.
"We have got two group games left and we're very confident we can do well in those. We know what these tournaments are like, if you can get on a run, if you can get a few guys going you can win these tournaments and it's not out of our grasp."
The win was England's first at the tournament so far.