Was Abram polytheistic

Answer 1

As an infant and toddler, his family indoctrinated him in the prevalent idolatry, yes (Maimonides' "Yad," Avodat kochavim 1:1-2). Abraham (Abram) soon repudiated their idols, however, upon thinking the matter through and concluding that there must be One God (ibid). See also:

http://judaism.answers.com/jewish-history/a-biography-of-abraham

Answer 2

Yes, he originally seemed to be, but he ultimately abandoned polytheism and committed his life to monotheism. While Abram as a young man may have followed the polytheistic beliefs of his family, he does not seem to have been devout: The Bible and various commentaries indicate that he was skeptical about the idols his father and others worshiped.

In fairness to Abram (who became Abraham when he declared his loyalty to the One God), he lived in the ancient world, at a time when the dominant religions were either forms of polytheism, the worship of many gods and goddesses, or henotheism, a belief system with many deities, but one who is superior and considered the ruler over all the lesser deities. Ethical monotheism was a unique departure from the common ways of worship found among the Canaanites, Babylonians, etc. Whether or not one accepts the Abram/Abraham story as historically true, from a religious standpoint it was certainly a courageous decision when he rejected the familiar deities and decided to adopted monotheistic worship.