“I am a lover of liberty. I will not and I cannot serve a party.”

Speech delivered at the second congress of the peace partisans (April 14, 1959).
Principles of the 14th July Revolution (1959)

"La Commune de Paris et la notion de l'état" (The Commune of Paris and the notion of the state) http://libcom.org/library/paris-commune-mikhail-bakunin as quoted in Noam Chomsky: Notes on Anarchism (1970) http://pbahq.smartcampaigns.com/node/222
Context: I am a fanatic lover of liberty, considering it as the unique condition under which intelligence, dignity and human happiness can develop and grow; not the purely formal liberty conceded, measured out and regulated by the State, an eternal lie which in reality represents nothing more than the privilege of some founded on the slavery of the rest; not the individualistic, egoistic, shabby, and fictitious liberty extolled by the School of J.-J. Rousseau and other schools of bourgeois liberalism, which considers the would-be rights of all men, represented by the State which limits the rights of each — an idea that leads inevitably to the reduction of the rights of each to zero. No, I mean the only kind of liberty that is worthy of the name, liberty that consists in the full development of all the material, intellectual and moral powers that are latent in each person; liberty that recognizes no restrictions other than those determined by the laws of our own individual nature, which cannot properly be regarded as restrictions since these laws are not imposed by any outside legislator beside or above us, but are immanent and inherent, forming the very basis of our material, intellectual and moral being — they do not limit us but are the real and immediate conditions of our freedom.

Letter to Princess Lieven (18 August 1828), reprinted in Guy Le Strange (ed.), Correspondence of Princess Lieven and Earl Grey. Volume I: 1824 to 1830 (London: Richard Bentley and Son, 1890), p. 130.
1820s

In an interview following her election as Deputy Leader of the Labour Party http://www.timesonline.co.uk/tol/news/politics/article2843875.ece, 10 November 2007.

Source: Richard III

Letter (April 1851)

Speech: “I Speak to You as an American Citizen” speech, Oct. 1, 1870, Douglas Papers, ser. I, 4:275
1870s

Speech delivered at the second congress of the peace partisans (April 14, 1959).
Principles of the 14th July Revolution (1959)

Variants: I don't belong to an organized political party. I'm a Democrat.
I belong to no organized party. I am a Democrat.
Source: Will Rogers, Ambassador of Good Will, Prince of Wit and Wisdom (1935), Ch. 9 "Rogers was a lifelong Democrat but he studiously avoided partisanship. He contributed to the Democratic campaign funds, but at the same time he frequently appeared on benefit programs to raise money for the Republican treasury. Republican leaders sought his counsel in their campaigns as often as did the Democrats." ~ P. J. O'Brien