Close Elections Reflect Robust Democracy
Here is a good article by a Harvard professor about the Mexican election. Close elections, whether in Mexico or the United States are not symptomatic of an electoral system is crisis, as is so often claimed in the mainstream press. Close elections are a sign that candidates are battling for popular support. That's robust democracy. There will always be instances of irregularities or fraud, and these become more important if the election is close. But close elections bring more public scrutiny in response, which benefits the system.