The topic and question of, does Google manipulate their search results based on political influence is nothing new. We asked the question at least once here. But this is the first time I have seen a Google Webmaster representative reply directly to that question.
JohnMu, a Google Webmaster representative, said in a Google Webmaster Help thread:
I can assure you that at Google we are not interested in manually moving sites up and down in the search results for political reasons. We wouldn't have the time for it anyway, it doesn't scale. Our search results are created algorithmically and this can and will result in changes over time, that's completely normal and to be expected. Additionally, we are constantly working on our algorithms, there are changes and tweaks almost every day. There is no "right configuration" that will guarantee that your site remains at any given position for the long run.
This is a strong statement saying Google does not manually move sites up and down for political reasons. Not only does Google not do this manually, but they do not do it algorithmically. So if it is not algorithmic or manual, then Google has no political bias in the search results.
Do you believe it? I can point to how Google left the offensive Michelle Obama image live, even though we know the owners and CEO are very pro-Obama. At the same time, you can say that not removing the image due to not wanting to appear politically bias, is in itself a bias on a political nature?
Forum discussion at Google Webmaster Help.