Y'all Probably Already Know This, But...
In this post at Volokh Conspiracy the poster makes the frequent but inaccurate claim that the Nazis were democratically elected to power in Nazi Germany. I've probably already covered this territory here before, but since I wrote a rather lengthy comment over there, I thought I would repost it here:
The OP makes an inapt comparison between voters in Germany voting the Nazi Party into power and Palestinian voters voting Hamas into power. As detailed in Henry Ashby Turner Jr.'s book Hitler's Thirty Days To Power, the Nazi Party never won a majority in any national election in Germany and Hitler was never elected to any government post. But, though in December of 1932 he looked to be finished politically in Germany, through a series of inspired back-room political dealings and gross miscalculations and undersestimation of him by by his political enemies, Hitler managed to get himself appointed Chancellor of Germany by aging and ailing President Hindenberg (Hindenberg, the President, incidentally, was elected).
Sure enough, after Hitler managed to consolidate power, set fire to the Reichstag and kicked most non-Nazi members of the legislature out, and then assumed the duties of both the President and the Chancellor without an election when Hindenberg died, he became wildly popular and probably would have won an election, but in the event, the fact is that the Nazis never won a national election in Germany, never won a majority of seats in Reichstag, and never won an election for President. Hitler took power by getting an aging and addled war hero President to appoint him to the Chancellorship. The Nazis were not elected democratically, though they eventually enjoyed wide support.
Though, since many of the economic policies and reforms that Hitler got credit for after he ascended to power were actually put in place by preceding Weimar governments, it is unlikely that the Nazis would ever have ascended to power without having it handed to them by Hindenberg. Once in power, the Nazis greatly benefited from being at the top to create support they could not have garnered otherwise.
One further note: Though at various times and to various levels of effect the Nazis played down their antisemitism when it suited them, they were never all that shy about their intention to destroy European Jewry. As a commenter above noted, the failure wasn't in the Nazis making the destruction of the Jews a plank in their policy, but rather in the world believing the Nazis would actually follow through on it.
Or, in some cases, a failure in the German people and the world to do its homework. For, while Hitler did spell out his intention to destroy the Jews (referring to them as a bacillus to be wiped out) in Mein Kampf, and post-1933 a majority of German homes (and the homes of every Nazi Party member) contained a copy of the book, it was so poorly written, boring, and difficult to get through that it was commonly joked amongst high-ranking Nazi functionaries that it was the most-purchased but least-read book in the Reich.
In any case, comparing the Palestinians electing Hamas to the Germans electing Hitler and the Nazis is an inapt comparison that fails to make the original poster's point. Nazi Germany is an example of a democratically-elected government turning power over to a violent, dictatorial government, ala Star Wars, not an example of the people of a democracy choosing an organization with a history of terrorist activity as its democratically-elected government.