The changing patterns of political engagement present a methodological challenge for the study of political behavior. Citizens have to an increasing degree abandoned partisan forms of political participation in favor of issue-based action. At the same time, the political action of younger generations is facilitated, or even enhanced, by constantly evolving information and communication technologies (ICTs). Moreover, the decreased feeling of civic duty is not only reflected in a decline in voter turnout. Survey researchers have noticed an increased reluctance among the general public to answer questions performed via traditional channels, i.e. through face-to-face interviewing, mail-in and telephone surveys. Thus, survey experts have in many countries turned to the Internet as a channel for gathering data on political participation.

In the present chapter, we analyze data from a Finnish probability based online panel survey. The survey was conducted in conjunction with the parliamentary election of 2011. Specifically, we focus on the representativeness and attrition of the panel. We look at socio-demographics and at variables pertaining to political behavior and opinions. Comparisons are made between the online panel and two other probability based surveys; the Finnish National Election Study which was conducted through face-to-face interviewing, and a telephone survey. We show that especially the process of recruiting respondents to an online survey is a difficult task, making the representativeness of the surveyed sample vulnerable to coverage, non-response and attrition. When it comes to population estimates, the online panel is skewed toward voting, even more so than the face-to-face and telephone surveys.