Who Knows 1?

The idea that there is only one God or that other gods are false and have no super natural powers seems to appear more prominently in D than the other sources. I'm hesitant to here give definitive numbers, firstly because I can't look this up in a konkordansia and secondly because there are many border line verses. But, in any case, as far as I know, that idea never appears in JE or P (to my knowledge, would could easily be mistaken). It appears 5 times (again, that I know of, could easily be missing some) in D as follows:

Deut 4:35
אַתָּה הָרְאֵתָ לָדַעַת, כִּי יְהוָה הוּא הָאֱלֹהִים: אֵין עוֹד, מִלְּבַדּוֹ.
Deut 4:39
וְיָדַעְתָּ הַיּוֹם, וַהֲשֵׁבֹתָ אֶל-לְבָבֶךָ, כִּי יְהוָה הוּא הָאֱלֹהִים, בַּשָּׁמַיִם מִמַּעַל וְעַל-הָאָרֶץ מִתָּחַת: אֵין, עוֹד
Deut 6:4
שְׁמַע, יִשְׂרָאֵל: יְהוָה אֱלֹהֵינוּ, יְהוָה אֶחָד
Deut 28:64
וֶהֱפִיצְךָ יְהוָה בְּכָל-הָעַמִּים, מִקְצֵה הָאָרֶץ וְעַד-קְצֵה הָאָרֶץ; וְעָבַדְתָּ שָּׁם אֱלֹהִים אֲחֵרִים, אֲשֶׁר לֹא-יָדַעְתָּ אַתָּה וַאֲבֹתֶיךָ--עֵץ וָאָבֶן.
Deut 29:16
וַתִּרְאוּ, אֶת-שִׁקּוּצֵיהֶם, וְאֵת, גִּלֻּלֵיהֶם--עֵץ וָאֶבֶן, כֶּסֶף וְזָהָב אֲשֶׁר עִמָּהֶם.

There are also 4 verses in shiras haazinu which may or may not be considered part of this category.

Deut 32:12
הֵם קִנְאוּנִי בְלֹא-אֵל, {ר}כִּעֲסוּנִי בְּהַבְלֵיהֶם
Deut 32:17.
יִזְבְּחוּ, לַשֵּׁדִים לֹא אֱלֹהַּ-- {ר}אֱלֹהִים, לֹא יְדָעוּם;
Deut 32:21.
הֵם קִנְאוּנִי בְלֹא-אֵל, {ר}כִּעֲסוּנִי בְּהַבְלֵיהֶם.
Deut 32:39
רְאוּ עַתָּה, כִּי אֲנִי אֲנִי הוּא, {ר}וְאֵין אֱלֹהִים, עִמָּדִי: {ס} אֲנִי אָמִית וַאֲחַיֶּהרְאוּ עַתָּה, כִּי אֲנִי אֲנִי הוּא, {ר}וְאֵין אֱלֹהִים, עִמָּדִי: {ס} אֲנִי אָמִית וַאֲחַיֶּה

The status of shiras haazinu is unclear according to DH. It is clearly not part of JE P or D. But, it is unclear if it is a completely different source added by the redactor (unlikely) or, (more likely) another source that D Incorporated into his book. In that case, the fact that this seems to be a theme of shiras haazenu fits in well with the fact that D used this song.