I think the Granny vote is a sign of changing times.
A few years most would have worried about a gay grandson/ son/ nephew... but these days every sad or lonely granny wants one.
Good company, stays in touch, helps with the house, chats and watches Corrie with you.
So Chris gets their vote. Add in a bit of Liverpudlian redial and the votes of those who see it as an hilarious anti-Cowell protest.
Perhaps Chris will finish 2nd - it's only when the 'anyone but Chris' vote joins in that he will be stopped.