Dave Hancock has been chosen by caucus members to serve as interim premier until a new leader can be elected to replace Alison Redford.

Hancock was deputy premier while Redford was in power, so it seemed to be the obvious choice.

In a shocking development to cap off weeks of controversy, criticism, and defections, Redford announced on Wednesday evening that she was resigning.

While it wasn’t totally unexpected, few believed it would have happened this quickly.

“And that is why I’m announcing today, I am resigning as Premier of Alberta, effective this Sunday evening,” she told the media gathered at the legislature on Wednesday.

Redford said that the recent controversy has weighed heavily on her mind and she was honoured to serve the province for the past two and a half years.

A poll on Wednesday showed her approval rating was very low, sitting at just 18 percent.

The party itself came down along with Redford, earning just 19 percent voter support, under half the support the Wildrose received in the same poll.

Danielle Smith says she doesn’t blame Redford for the failure, but the party itself. “Alison Redford was elected to run the PC Party as an outsider. She wasn’t part of the old boys club. The problems with their party and their government run far too deep for one leader to change. No matter how noble their intentions are or how deeply they’re committed to them.”

The party will now be looking for a new leader, the third in as many years.

A number of names have already come to mind.

Among them: Alberta Finance Minister Doug Horner, Deputy Premier Dave Hancock, Justice Minister Jonathan Denis, former Edmonton mayor Stephen Mandel, past federal cabinet minister Jim Prentice and former provincial treasurer Jim Dinning, who lost a leadership bid for the party in 2006.

Keith Brownsey, a political science professor at Calgary's Mount Royal University, said Mandel and Dinning may be the best choices for the Tories, but they may not want to run a party that's sinking after four decades in power.

"Really, this is a party in free fall. It's a party that has tossed its last four leaders," he said.

"Who'd want to take that job?"

Mount Royal University political scientist Duane Bratt says Horner is the man to beat.

"He's the finance minister who just put together a fairly good new budget, a former leadership contender, deep roots in the party. My money would be on Doug Horner right now."

Stephen Carter, the man who helped launch Redford into power in the first place, says the position is a tainted one.

“Maybe someone enters from the outside but any of the current MLAs who are party to this disaster, they don’t deserve to be leading at this particular point.”

The party is now organizing an interim order of succession and, within six months, will select a new leader and a new premier.

Redford’s term as premier is the second shortest in the province’s history at two years, five months.

Richard Gavin Reid, with the United Farmers, served for just one year, two months in 1934-35.

(With files from CTVNews.ca)