Let me take you back to 1971, the last year when the political grounds shifted underneath Alberta with the election of Peter Lougheed's Progressive Conservatives over the dynastic Social Credit Party led by Harry Strom, but more famously led by Ernest Manning for decades before his resignation in 1968.
In this election, for which you can watch interesting video clips from the CBC archives on and see some of the flyers for on daveberta's website, Social Credit lost its grip on Alberta's politics as Lougheed, then a young, fresh new face in politics. Lougheed didn't necessarily promise much more different from Premier Strom and Social Credit, but the governing party, which had first won power under William Aberhart in 1935, was seen as tired, decrepit, and no longer as in-tune with the province's needs and goals. This was a time when Alberta was booming with oil revenue and looking for a greater role in the Canadian federation that, according to Lougheed himself, Social Credit couldn't provide.
Harry Strom, elected SC leader in 1968, was known as "decent" and "honest," though he didn't have the charisma that Manning nor Lougheed had. He was caught defending an ancient and tired regime, and didn't have the political skills necessary to keep Lougheed and the PCs at bay. It's a fascinating short read of his tenure and style on Wikipedia if you're inclined.
The NDP, led by Grant Notley, took over 10% of the vote in this election but weren't a threat in any where. Only Notley was elected to his seat in northern Alberta, Spirit River-Fairview.
The Liberals were in terminal decline at this point since their previous high of 15 seats and 30% in 1955, and leader Bob Russell only managed 1% of the vote - and this was pre-NEP. The Liberals suffered due to Lougheed's centrist-sounding platform (or at least less right-wing platform compared to Social Credit) of the time.
Strom, who represented Cypress in the southeast corner of Alberta, probably benefited from being from the region, as well as being Social Credit's "core region." In this way, the Wildrosers are similar; their best region is southern Alberta including portions of Calgary, and could easily sweep the same regions as Social Credit this coming April 23rd.
The Progressive Conservatives earned most of their support in central Alberta and Edmonton. To this day, the strongest regions for the PCs have been central Alberta, though Edmonton has been a weaker area for the party since the NDP and Liberals rose up as the main opposition parties, and especially since 1993's "Redmonton" sweep by the Decore Liberals. Between 1986 and 2008, the majority of Edmonton's seats went to the opposition. This year, central Alberta remains the biggest boon for the PCs, while Edmonton is closer though still favoured to go PC.
One can draw a lot of similarities between 1971 and 2012 - an old regime, an untested leader, a charismatic challenger, relatively weak third parties, and a booming economy. Like 1971, Alberta is looking for a new direction. Peter Lougheed believes in Alison Redford's vision of Alberta as the new force of Confederation, while lambasting Danielle Smith's "insular" ideals as comparative to Strom and Social Credit's. Yet the PCs have moved far from being a simple "right-wing" party to something too comfortable in its position, while one can argue the Wildrosers embody the theme of "change" and "Alberta First," something the province's residents are all too happy to latch on to.