I make a distinction between ideology (what people believe or profess to believe) and culture (the learned habits that determine how people actually behave). The two can find themselves at cross-purposes. Think of an avowed socialist who underdeclares his or her income in a country where tax evasion is common, or a conservative rule-of-law type who pulls strings to evade prosecution for traffic offences in a country where people with connections have that option. As these examples show, culture is a more fundamental determinant of how most people behave than ideology. Seems to me Whitehead's article is more about democratic ideology than democratic culture.

If "democratic culture" means a popular culture that is supportive of democracy and sustains democratic political institutions, I suspect that a key issue may instead be whether the majority of voters are lifetime supporters of their political parties or whether they are willing to vote for a different party, and if so what sort of considerations might induce them to do so. I suspect that corruption and misgovernment are more prevalent in democracies where lifelong party loyalties predominate, even if parties alternate in government, whereas in democracies where people are more willing to switch their vote there is more accountability and corrupt or incompetent ministers are more likely to get sacked. Party-switching by voters encourages greater accountability and cleaner government because it compels governments to respond to scandals in order to minimise the loss of votes.