Well, the most pure version of a Deistic God wouldn’t necessarily have to be perfectly omnipotent, merely potent enough to have created the Universe. Exactly how potent that is isn’t really clear, since of course we have no idea how to go about creating universes. (Perhaps the noted theologian Gary Larson was closer to the truth than we know.)
Christians and Jews of course do believe in God’s perfect omnipotence. Atheists tend to find this causes logical problems, no matter how carefully defined, especially when mixed with other divine attributes like omniscience, omnibenevolence, and free will, or with human free will. These divine attributes also occasionally seem to run afoul of the most literal reading of some Biblical verses, as Genesis 3:8-9, Judges 1:19 (especially in the King James translation), or Matthew 24:36 (a potential problem for Christian Trinitarians).
To begin with, Christian and Jewish theologians would cite the Bible to support the idea of divine omnipotence or perfect almighty power. The 1917 Catholic Encyclopedia article on “Omnipotence” cites several Biblical passages, including Job 42:2 (“I know that you can do all things; no plan of yours can be thwarted.”) and Matthew 19:26 (“Jesus looked at them and said, ‘With man this is impossible, but with God all things are possible.’”) plus the very similar Mark 10:27 and Luke 1:37, and two verses from what Protestants would consider to be the Apocrypha, Tobias 13:4 (“Because he hath therefore scattered you among the Gentiles, who know not him, that you may declare his wonderful works, and make them know that there is no other almighty God besides him.” – I guess it’s the “almighty” they’re stressing, which in the Latin Vulgate is actually translated “omnipotens”) and Ecclesiasticus 1:8 (“ALL wisdom is from the Lord God, and hath been always with him, and is before all time”, which stresses the related notion of divine omniscience.)
Chapter II of the Presbyterian Westminster Confession of Faith (1648) declares God to be “almighty” and gives as proof texts Genesis 17:1 (“When Abram was ninety-nine years old, the LORD appeared to him and said, ‘I am God Almighty’ ; walk before me and be blameless.”) and Revelation 4:8 (“Each of the four living creatures had six wings and was covered with eyes all around, even under his wings. Day and night they never stop saying: ‘Holy, holy, holy is the Lord God Almighty, who was, and is, and is to come.’”). The Genesis passage includes the Hebrew word Shaddai, meaning “almighty”; the Old Testament’s numerous references to God by this name or title was also noted by the 1917 Catholic Encyclopedia. The Latin Vulgate translation renders the phrase “Lord God Almighty” from Revelation 4:8 as “Dominus Deus omnipotens”.
In addition to Scriptural references, I suspect that the Catholic Church (and probably all Christian traditions to some extent, even very Biblically-oriented Protestant ones) would also proclaim their monotheistic God’s perfect omnipotence on the basis of what they consider to be philosophical or theological first principles; see the 1917 Catholic Encyclopedia article above.