As of September 9/22/2015, no live official trademarks were found on USPTO.gov for the exact term
Debate Tonight can occur every night -- and day, for that matter.
Moreover, during "silly season" (definition: the l-o-n-g slogging campaigning that goes on in the U.S. for two years before a presidential election), this domain becomes especially valuable, especially prior to debates among candidates of both political parties.
And "silly season" is NOW.
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