Allow me to answer using the original situation of vote tracking. Yes, such a claim would get my attention.
Would I choose to believe it? I believe it if there is proof of it happening.
What do I think it says of the incumbent party? It shows that people actually believe that the party would deploy such tactics, and would vote out of fear.
I am not clutching at straws here, I am a civil servant and and a substantial number of my collegues supported the incumbent party more out of fear for their rice bowl.
Of course, I'm not saying that the incumbent is resposible for spreading these myths, if people actually believed that they are whiter than white, then why do these myths endure?
Or in your analogy, if Canon has proven itself with a track record, any false accusations will fall sooner or later.