TMZ.com

Singer Loomis Butchers National Anthem at Live Event, Begs for Do-Over | TMZ Live

As you can see, the singer starts off strong at the Free and Equal Elections Presidential Debate on Thursday ... but quickly goes off-key, losing her cool and begging into the mic, "I f***ed it up, I f***ed it up. Can I go back, can I go back please?"

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