Challenged by Henry Tudor, Richard was killed at Bosworth in 1485 after only two years on the throne.

BBC: Richard III dig: DNA confirms bones are king's

What happened two years is Ciro Rodiguez was a liberal, let's say a liberal Democratic congressman, and he's being challenged at the primary by Henry Cuellar, who's more of a moderate conservative.

NPR: Political Wrap: DeLay Primary, Domestic Wiretapping

And when Vice President John Nance Garner challenged Roosevelt for his third term in 1940, Garner was off the ticket and Henry Wallace was named to the ticket.

NPR: Political Junkie: Three Weeks to Pennsylvania