DES MOINES, Iowa — The Powerball jackpot jumped to $550 million on Thursday — the third largest lottery in history — as dreamers snatched up tickets for the minuscule chance at a life on easy street.

Thursday’s announcement by the Iowa-based Multi-State Lottery Association means ticket sales have soared since Wednesday night’s drawing for an estimated $360 million jackpot, in which no one picked all six numbers correctly.

Sales jumped by $260 million in the days before November’s biggest Powerball jackpot win in history — a prize of $587.5 million. And Iowa Lottery spokeswoman Mary Neubauer said it’s possible that Saturday’s could end up eclipsing that amount.

A $550 million jackpot would be the second largest in Powerball history and the third largest for any lottery.

Lottery officials expect jackpot totals of this size to continue to climb in shorter amounts of time, thanks in part to a game redesign in January 2012 that increased the odds of winning some kind of prize, but also lowered the possible number combinations to win the Powerball.

There’s also “cross-selling” of Powerball and Mega Millions tickets — states being able to sell both Powerball tickets and Mega Millions tickets — that began in January 2010. As a result, large jackpots will continue to surpass all-time jackpot records set years ago, said Neubauer.

“It usually took a handful of months, if not several months, for a jackpot to reach this large amount,” she said. “Now it’s achieving that within a handful of weeks. I think the redesign is achieving exactly what we had wanted it to achieve, which is the bigger, faster-growing jackpot.”