in+touch+with+Snowball+ever+since+his+expulsion

This is like even after Lenin's death; people still come to Red Square (where Lenin is preserved) to see him. And even though he is dead his work that he had done and the sparks that he created within his people/followers still lived on and were continued even after his death. For example, two groups with the names of the Bolsheviks and the Mensheviks meet and ponder what Lenin would do next and think like him so as to continue running their plans as if Lenin were still there/alive. In //Animal Farm//, even after Snowball has been chased out of the farm, some animals still see him and carry out his plans.

-Erika Flores

"This was the start of a major purge of the Party. To purge the Party meant expelling members who, in one way or another, were unreliable. The Party Central Committee sent letters to branches all over the USSR, ordering them to check the reliability of the members and, especially, to find out whether they had ever been **supporters of Trotsky**." p.16 - This draws a specific parallel with how the pigs are being punished for being in "touch with Snowball." Snowball, who is in this novel a representation of Trotsky, is being accused of scheming against the A.Farm, and anyone Napoleon doesn't like is forced into testimonials saying they have sided with Snowball (just like Stalin did during the Great Purge mentioned above.)