(while poll workers try to figure out why he's the only one voting): "My cat's breath smells like cat food." And later, when asked who he's voting for: "Ralph Wiggum vote for... the new purple flag. And free juice boxes." If you actually meant "Dthrip" as a character name or a specific quote — that doesn't appear in Season 19. Could you clarify if you meant "The Thrip" or a different episode? I’m happy to find the exact scene you’re thinking of.
If you're looking for a notable moment — here's a from that episode involving "d-thrip" (which I think is meant to be a phonetic misspelling of "The Thrip" — a tiny insect or possibly a mishearing of a gag): the simpsons season 19 dthrip
That episode features accidentally becoming the deciding voter in a presidential primary after Springfield holds an early election to get fast food franchises to compete for their votes. (while poll workers try to figure out why
It sounds like you're asking for a clip or specific piece from episode titled "E Pluribus Wiggum" (original air date: January 6, 2008). Could you clarify if you meant "The Thrip"