What is the Biblical basis for the belief that Jesus is Michael? Congregations such as the Jehovah's Witness and Seventh day Adventists believe that Jesus is Michael. What is the Biblical basis for the belief that Jesus is Michael?

Jehovah's Witness


  ...it is logical to conclude that Michael is none other than Jesus Christ in his heavenly role. Source


Seventh day Adventists


  Moses passed through death, but Michael came down and gave him life before his body had seen corruption. Satan tried to hold the body, claiming it as his; but Michael resurrected Moses and took him to heaven. Satan railed bitterly against God, denouncing Him as unjust in permitting his prey to be taken from him; but Christ did not rebuke His adversary, though it was through his temptation that the servant of God had fallen. He meekly referred him to His Father, saying, "The Lord rebuke thee." 


Early Writings, p. 164.
The Seventh Day Adventist view

The SDA view is well articulated here: Amazing Facts: Who Is Michael The Archangel?

The primary arguments involved are:


There are appearances of the preincarnate Christ with titles of “Angel of the LORD”, “Angel of His Presence” and “Angel of the Covenant”.
The meaning of angel has a wide range of interpretations (it literally means “messenger”).
The use of echad in Daniel 10:13 can mean “one” or “first”, so one interpretation is “Michael, the first of the chief princes” (rather than “one of”).


One note that is important regarding the SDA view is that they do not deny the deity of Christ, but teach that the title “Michael the Archangel” is another title for God the Son in the same vein as “Angel of the LORD” or “Captain of the LORD’s Host.” 

From the conclusion:


  In conclusion, we see this majestic and mysterious being, sometimes
  called Michael, sometimes the angel of the Lord, sometimes the
  commander of the Lord’s army, veiling His divinity and appearing in
  the form of a humble angel. Yet this same enigmatic being has the
  power, authority and attributes that belong only to God. He evicts the
  devil from heaven; He resurrects the dead; He intercedes for the
  saints; He judges and then stands, launching the great time of
  trouble. He redeems the saints and receives their worship. He offers
  us a new name.


The Jehovah’s Witness view

The JW view is articulated here: Is Jesus the Archangel Michael?

The principle arguments are:


The custom of having more than one name is common in the Bible.
Arch in archangel means “principal” or “chief.”
The word “archangel” is never used in plural form (therefore it describes a unique being).
Jesus spoke of his preincarnate existence.


From the conclusion:


  So Michael the archangel is Jesus in his prehuman existence. After his
  resurrection and return to heaven, Jesus resumed his service as
  Michael, the chief angel, “to the glory of God the Father.”


The two views are actually quite similar regarding the use of “Michael the Archangel” as yet another title for Christ. 

The two groups differ, however, regarding the deity of Christ. Jehovah’s Witnesses explicitly deny his deity, arguing He was the first of God’s creations and placed in authority over it. He is a created being, albeit the most powerful being short of God himself.

Note: This latter view has always been considered the aberrant view in Christianity. While the SDA view would fall within the camp of orthodoxy, the JW view does not.