The fragility of information aggregation in large elections

In a common-values election where voters receive a signal about which candidate is superior, suppose there is a small amount of uncertainty about the conditional likelihood of the signalʼs outcome, given the correct candidate. Once this uncertainty is resolved, the signal is i.i.d. across agents. Information can then fail to aggregate. The candidate less likely to be correct given agentsʼ signals can be elected with probability near 1 in a large electorate even if the distribution of signal likelihoods is arbitrarily near to a classical model where agents are certain that a particular likelihood obtains given that a specific candidate is correct.