The Lionesses looked to be heading out of the competition when losing against Russia in Linkoping on Monday night, but a stoppage-time equaliser from Everton's Toni Duggan secured a positive result which leaves fate in their own hands.
Victory over France, who have already secured their spot in the last eight as Group C winners, would see England progress as one of the two best third-placed teams at the very least, while results elsewhere mean a draw could still also be enough or even see the quarter-final line-up completed by lots.
England have not beaten France since 1974, but Powell feels that could just work in their favour as they look to make history.
"We know it is a mountain, we know who we are playing, we know who we are up against, but we have got to get something out of it," said Powell.
"Sometimes it is easier playing teams you are not expected to beat, sometimes it takes a little bit of pressure off. We are in a fight now.
"We need to prepare as best we can and we have got to go again."
Right-back Alex Scott earned her 100th cap against Russia.
The Arsenal defender, 28, feels England, who lost their opening match against Spain to a last-gasp goal, can lift themselves for tomorrow's all-or-nothing showdown.
She said to FATV: "We showed character to come back in the game once again, but we can't keep doing that at this level.
"We have to take the positives; at least we have still got a fighting chance in this tournament and that is the main thing."
Chelsea Ladies forward Eniola Aluko challenged her team-mates to raise the bar against France.
"If you look at both games against Spain and Russia we create chances, that's not a problem with this team," she said.
"It's about making it count and making the keeper work a bit more. The focus is on attacking and making sure we score.
"[There is] a willingness to do something special against France and get three points.
"We have shown character, we have shown fight. Hopefully we will have that fighting spirit against France."
Meanwhile, it was announced this afternoon that Bournemouth will host England Women's opening 2015 World Cup qualifier against Belarus in September, which will be broadcast live on the BBC.