Following their defeat in the one-off Test at Trent Bridge and a tense final-over loss in the opening T20I at Edgbaston on Saturday, Heather Knight's team now need to win each of their remaining five white-ball matches to overturn a 6-0 points deficit, and win back the Ashes for the first time since 2015.
"We've seen weirder things happen than that in cricket," Ecclestone said. "We're up for the challenge, we know exactly what we need to do. We're really not far away from them. They're a great team and we compete with them a lot, but we have to go one better tomorrow.
"It's obviously going to be a really hard task to beat the Aussies, five out of five, but we know what we need to do and the girls are up for it tomorrow. So we're hoping to put on a big show in front of the big crowd."
The Ashes to date has been notable for a significant crowd turnout, with the series predominantly being staged at Test-match venues. The Test attracted in excess of 23,000 across the five days, while a further 19,527 attended the Edgbaston cliffhanger.
"It's absolutely amazing," she said. "To see so many kids in the crowd, so many people watching our games has been amazing. I think [Edgbaston] is the largest crowd I've ever had in the UK, so hopefully it continues.
"I know we've got sell-out crowds at the Oval and Lord's, and I'm just so excited to get out and play cricket there in front of them. It makes all the hard work on and off the field worth it. I think we're just really excited to get there and entertain them, and hopefully inspire the next generation to play cricket."
Ecclestone has provided plenty of the inspiration herself. Her hard-earned ten-wicket haul in the Test spanned a remarkable 77.4 overs, while she was also the pick of England's bowlers at Edgbaston with 2 for 24 in 3.5 overs, including three consecutive dot-balls to ramp up the pressure with the scores level in the final over.
And as England's star bowler, she has noticed an increased determination on Australia's part to take her on in this series, a trait that she hopes will play to her advantage as the series wears on.
"A few Ashes ago they just didn't go against me and looked to block me out, but they've definitely taken more of an attacking approach, so I think it's exciting for me," she said. "I feel more in the game when they come at me and not look to block me out.
"We've had conversations and a few meetings about how we want to go about our cricket tomorrow. We're really confident going into it and hopefully we can pull it off."
Andrew Miller is UK editor of ESPNcricinfo. @miller_cricket