In provincial politics, the political differences are more noticeable. The Social Credit Party of Alberta dominated most of Alberta's ridings, including Edmonton and Calgary, for most of the time it governed from 1935 until 1971. When the Progressive Conservatives under Calgarian Peter Lougheed won election in 1971, they would go on to dominate both cities' ridings themselves until 1986, when the Alberta New Democrats and Alberta Liberal Party made a breakthrough in Edmonton. For the next three decades, the Tories continued to win a majority of seats in every election both province-wide and in Calgary, but gained a majority of Edmonton's seats only once (in 2001) while the party had a Calgarian as leader.