The things is, more people didn't vote for him than did. In a proportional system, the Tories would not be in power. It's a quirk of geography and how their support is spread that is giving them this much power. A proportional system would return the majority of votes to left wing parties but it fails in a first past the post system because the vote is split across 4 parties (Labour, Lib Dem, Green & SNP in Scotland) whilst the right wing vote is basically in 1 party. The UK has the majority consistently voting left but consistently getting right wing government.