Learn English – Why does “I am in your debt” mean the opposite of what it suggests

There is also a political overtone to the use of this phrase. It is not normal to have two responses, one from a party followed by another from a subgroup within that party.

Hence the user of the term may be referring to his belief that this split in the republicans is their entire party's ticket to oblivion. Not just the time-worn habit of the responding speaking being destined to obscurity.

I think what is going on in the Urban Dictionary definition you found is a description of someone at a carnival who is purposefully using reverse psychology in an attempt to actually get more people inside. I'm getting this from the definition's example sentence (Carnival Barker- "Don't go in there man it's haunted.") For example, such a carnival barker may target a man and a woman on a date. By saying to the man, "don't go in there, it's too scary," he could be seen as indirectly questioning the guy's "manhood," thus convincing him to go in and prove himself.

This is an admittedly confusing definition of carnival barker. For future reference, Urban Dictionary is often useful for very current slang and fun to play around with (try looking up your town or city), but it's not the best place for good definitions. Check out these "definitions" of Urban Dictionary at Urban Dictionary to get my point. And even for definitions of slang, be sure to check the poster's other entries for a sense of their credibility and take note of how many up vs. down votes their entry has.