Can a Christian Become a Baha'i?

William Miller says that the Bahá'ís have stolen their theology from Christianity. He writes:

[n]o religion has been so widely misrepresented in its presentation in the West... voluntary missionaries have represented the faith as an enlightened humanism with a new and original message of universal peace. As a matter of fact, there is not one truth in these Occidental representations of Baha'ism that is not borrowed from Christianity...

For more details, check "Can a Christian Become a Baha'i?" by Miller 

Samuel Graham Wilson, in his writings, offers an analogue to Miller's belief that Christians can not be Bahá'ís by enumerating six reasons for characterizing the Bahá'í faith as "antichristian":

1. It lowered Christianity to the same level as other religions.

2. The Bahá'í Faith claimed to supersede Christianity with a new revelation.

3. The Bahá'í Faith dethroned Christ and saw him as one manifestation of God among many.

4. It assumed falsely that Bahá'u'lláh is Christ returned.

5. It argued that biblical prophecies were fulfilled by Bahá'u'lláh and 'Abdu'1-Bahá.

6. It denied Christ's miracles and his bodily resurrection.

(The Bahá'í Faith and its relationship to Islam, Christianity, and Judaism: A brief history, Adam Berry)