Majoritarian electoral systems as well as proportional systems with small districts give an advantage to rightwing parties in the translation of votes into seats because these parties are more popular in rural areas where, under those systems, voters tend to be over-represented in parliament. We do not know however is the role that voters play in this relationship. Do they amplify the mechanical partisan effect of the electoral system or tone them down? To answer this question, we first analyze the CSES data that cover over 40 elections in Western Europe since 1996. We construct a measure of strategic voting by merging individual-level survey data with district-level electoral data. We then study what parties benefit from strategic voting overall, and across electoral systems and districts magnitudes. Second, to explore further the mechanisms at stake, we analyze data from lab experimental elections in the UK and France. The key advantage of this method is that the elections are conducted in an abstract context in which the left-right ideology of subjects (measured in a post-experiment survey) is by design uncorrelated with their strategic incentives in the lab elections. Hence, we can assess whether rightwing and leftwing subjects inherently behave differently when it comes to casting a strategic vote.