Stumbled across a number of swimlane diagrams developed by Andy Tow in 2012.
This one is for the Santa Cruz province and covers elections 1983 through 2011. More images like these for the Chaco, San Juan and Jujuy provinces are available. These are sample screenshots from the ‘Electoral Atlas’ (see below).
Each node represents elections, with the height of the block representing the percentage of votes/seats received. The “leading” party is always at the top. So the bands between two blocks are basically electoral behaviour and (may) visualize political shifts. When two bands join, there seems to be a coalition.
In this special type of Sankey diagram the nodes are of greater importance. The bands represent quantities, however there is a temporal rather than directional aspect to the flows.
Check the interactive version of the ‘Electoral Atlas’ by Andy Tow, where you can hover the mouse over the diagram to highlight details.