To whom do the "seven spirits of God" refer in Revelation?

Several passages in Revelation (Rev. 1 4; Rev. 3:1;Rev.5:6) refer to the “seven spirits of God.”

Interpretations vary.

To what do the “seven spirits of God” refer?

Poll Results

To whom do the “seven spirits of God” refer in Revelation?

The seven-fold ministry of the one Holy Spirit as per Isaiah 11:2 Votes: 15
Seven administrative angels (or church angels), perhaps same as those who blow the trumpets (for example) Votes: 2
The seven human messengers of the churches Votes: 0
Seven congregational leaders (of the seven churches) Votes: 0
Sometimes one of the above, sometimes another (double or multiple usage) Votes: 1
Undecided Votes: 4
Other (please specify in comments) Votes: 1