This is an interesring question with a rather large scope. I'm afraid I can only shed some light on one particular group of people. I would argue that economic insecurity had a large influence, though there are of course many factors that lead to such large parts of the population voting for the NSDAP. The political instability of the Weimar Republic as well as the Great Depression are commonly mentioned as causes for the rise of Hitler, but even they were not alone. If you look at the election results of November 1932 and March 1933 the gains of the Nazi party can be explained by the terror that preceded the elections and during which political opponents were terrorised by the SA and the NSDAP.

There exist a number of studies that have a alysed the election results and broken them down by various demographic, social, economic and geographic factors. To generalise one can say that the Nazis had a very broad appeal, and the election results reflect that. People from virtually all ages, regions and social standing voted for the NSDAP. However, some outliers can be identified: In the cities, the lower working classes and unemployed tended to vote for the centre-left SPD or communist KPD. In the south of Germany, which was (is) predominantly Catholic, people tended to vote for the centre Catholic Zentrum Party. Of course, though, we still see huge popularity for the Nazis.

One group which stands out particularly, especially before the 1933 elections, are northern and eastern German rural people. We have to remember that at the time, even though Germany was heavily industrialised in the cities, nearly half of the population was still working in the agricultural sector. By 1933, prices for agricultural products had barely increased form pre-1914 prices while the cost of living and farm equipment had increased significantly. Many agricultural products such as grains and meat were imported from overseas at lower prices than domestic farmers were able to match. As a result, many farmers were in hopeless debt. All attempts by the previous government under chancellor Brüning had shown little result. It remains unclear whether the economic improvement in the mid forties can partly be traced back to Brüning's effort or if his measures went by without any effect. In any case, large parts of the German population was faced with a tough economic situation.

The NSDAP recognised this and after initially focusing almost exclusively on the urban working classes quickly shifted its focus onto these farmers. After it became clear that many north and east German rural voters supported Hitler, he arranged for Richard Walther Darré to intensify the party's efforts in rural areas.

In some of these areas, the results are truly astonishing by modern standards: in a political system with many major parties, every second rural voter put their cross next to the NSDAP. Then again, almost all electoral areas, including the cities and industrial centres in the west, overwhelmingly voted for the Nazis. We see results around 40% in such places.

To summarise: Since so many people voted for the Nazis, it isn't easy to point out clear groups and the economic condition in Germany at the time provide context and are a key part in the explanation to Hitlers rise to power, but certainly aren't the only or even major cause. However, many Protestant farmers voted for the NSDAP, while many urban workers and Catholics did not.

Tips for reading:

The Plough and the Swastika: The NSDAP and Agriculture in Germany, 1928–45 by J.E. Farquharson, London, 1976.

Jürgen W. Falter, Thomas Lindenberger, Siegfried Schumann: Wahlen und Abstimmungen in der Weimarer Republik. Materialien zum Wahlverhalten 1919–1933. München 1986.

Daniela Münkel: Nationalsozialistische Agrarpolitik und Bauernalltag. Frankfurt, 1996.