What's Up with Salt River and Antebellum Political Cartoons?

If you spend any appreciable time viewing antebellum political cartoons, you are likely to run into mentions of Salt River. But, where is this Salt River and why was it used so often by period cartoonists?  

Salt River is an actual geographical feature of the state of Kentucky. It runs 150 winding miles from central Kentucky and empties into the Ohio River in Hardin County, just south of Louisville. 

So, how did it come to be associated with politics - especially presidential candidates? There are several stories that explain the relationship between the river and the nation's highest office, but one stands out. The legend goes, that on a trip up the Ohio River, a Democratic boatman purposely delayed Whig presidential candidate Henry Clay from reaching a speaking engagement in Louisville by going up Salt River; thereby costing Clay an opportunity to gather valuable votes, and thus he lost the election. 

Whatever may be the true story, political cartoonists took the analogy and ran wild with it, especially  in the 1840s and 1850s. "Going up Salt River" became synonymous with reaching political oblivion; as the following cartoons show. Title links are supplied below each image for more information and interpretation by the Library of Congress.

  

Going Up Salt River

Matty Taking His Second Bath In Salt River

Inklings Of Travel, Up Salt River

Terrible Rout & Total Destruction Of The Whig Party, In Salt River

Polk & Co. Going Up Salt River

A Correct Chart of Salt River

Rowing Him Up Salt River

Fording Salt River