Hamas had the most votes of any party at 44%, with what you say to be 38% of the possible people who could have voted.
Funnily enough, in 1933 the Nazis also won the election with 44% of the vote, and that represented 38.6% of the potential voting population.
So following your supposed reasoning - and as per my comment above - should the allies have then tried to negotiate a ceasefire with the Nazis, and not have bombed them or marched on Berlin, because not everyone had voted for the regime?