What2Watch on Thursday Night

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10 pm on AMC: Only two episodes left in this season of Mad Men. This week on "Nixon vs. Kennedy," the staff pulls an all-nighter watching the presidential-election returns.

Mad Men Preview: Nixon vs. Kennedy 

8:30 pm on NBC: Will Arnett returns as Jack's network nemesis on 30 Rock.

8 pm on The CW: Pageant showdown on Smallville! It's Supergirl Kara vs. Top Model survivor Eva.