remember the roto-rooter song? "call roto-rooter, that's the name – and away go troubles down the drain [chorus: 'roto-rooter…er']".
there was a time when probably everyone in america knew the name of what may have been the first nation-wide plumbing company (please note that i'm just guessing that it had that status, i've not done any research to back that up). most people knew it, not because they had ever used or needed roto-rooter…but simply because of the ad jingle. it brought immediate recognition, whether used as a part of a visual commercial on tv, or as a radio ad.
think of some others…one that keeps leaping into my own brain right now is the cocoa crispies song. the one from when they had the little chocolate elephant as a mascot. "i love my cocoa crispies, they are so chocolate-y…that when i get a taste of them i trumpet happily![insert happy little trumpet sound]"
both roto rooter & cocoa crispies still exist. both of them have abandoned what were probably they're most successful ad campaigns ever (success being defined, in this case, by the level or name recognition involved). i'm pretty sure that cocoa crispies doesn't even use the cute little elephant as a mascot anymore.