What is an Elephant In The Room?

For those who may not be familiar with the phrase "Elephant In The Room" let me explain 2 ways, defintion and example:

Definition: The phrase is an old English Idiom that suggests something (a topic of discussion) is in the air and not being addressed. Another common and similar phrase would be the 8,000 lb gorilla in the room. The phrase also implies a value judgement that an issue needs to be discussed openly.

Example: (insert giddy snickers and chuckles) - Mike Huckabee has been the unmentionable candidate on many discussions for the last several months throughout the media (inclusive of Fox). In spite of all the discussion coming from Democrats to the contrary of Mike being the one to watch - Mike was simply ignored. In fact - Bill O'Reilly went so far to say that Mike would never make double digits in the polls (funny - I remember these same people talking about the unreliability of polls in the last two elections and following discussions of polls up with phrases like "if you believe the polls" - now the polls are the end-all to politics, making or breaking candidates, or so it seems).

Enter the Elephant (and if you've seen pictures of Mike Huckabee prior to his huge weight-loss as Governor of Arkansas - there's no correlation between the two). Mike Huckabee entered this race and not only climbed out of the trenches of "lower tier-ism" but became a 4th member of the upper tier - and still was refused to be recognized. I suggest that Mike Huckabee became the Elephant in the Room when he reached 10% in the polls (although probably way before then - I just have to start somewhere). Now the Elephant is not only in the Room - But he's just showing off now. Take a look at these Iowa Numbers (I mean - if you believe the polls):

Romney 26%
Huckabee 24%
Giuliani 11% (Wow - down from 15 earlier this week)
UNDECIDED 13% (If Thompson won over 1/2 of this - he would still be trailing)
Thompson 11% (hmm NRLC, still think your anti pro-life legislation candidate is worthy?)
Paul 4%
McCain 4%
Tancredo 1%
Hunter 1%