Do European Parliament Elections Impact National Party System Fragmentation?

Why have European large parties lost electoral ground in recent decades? Whereas most explanationsdraw on theories of dealignment, this paper advances a novel, institutional, argumentby focusing on the introduction of direct elections to the European Parliament (EP) in1979. Archetypes of second-order elections, EP elections are characterized by lower voteshares for 1) large and 2) incumbent parties. Bridging the second-order elections theory withtheories of political socialization, we posit that voting patterns in EP elections spill over ontonational elections, especially among voters not yet socialized into patterns of habitual voting.In so doing, they increase the national vote shares of small parties. This proposition is examinedusing an instrumental variables approach. We also derive a set of testable propositions toshed light on the underlying mechanisms of this pattern. Our findings show that EP electionsdecrease support for big parties at the national arena by inculcating voting habits