Mental Floss has a cool little collection of Famous Political Campaign slogans (We Polked You in ’44, We Shall Pierce You in ’52!). There's some snappy stuff - and there's more at Wikipedia. My all-time faves are "Tippecanoe and Tyler too" (just because it sounds good), and - of course - "Yes We Can".
Best ever, though, is the immortal classic: I Like Ike.