In acting there are basically two methods: representational and presentational. These are also employed in song performance. Most of the remaining contestants are presentational - meaning like Brian said in reference to Scotty, they sing just words, and/or stay in rhythm, and use facial gestures and movements that they've copied in order to enhance their performance. Basically then they're karaoke singers. The representational singers interpret the song and internalize it - taking the song and making it their own personal experience. Jacob is the only one who does this consistantly. I believe Casey has done it on some performances. And on fewer occasions, so has Lauren. The representational method is the most effective in moving people emotionally. However the motivation for casting votes is so varied - street team votes, votes based on looks, votes influenced by the judges, votes based on proving that one's original predictation should come true, on singing ability, creativity, entertainment value, I could go on - that it's hard to pick a winner in advance.

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