Stand By Your Internet Ad Act of 2004 - Amends the Federal Election Campaign Act of 1971 to: (1) apply to campaign communications transmitted through the Internet the same presentation requirements currently applicable to their counterpart authorized printed campaign communications, including communications expressly advocating the election or defeat of a clearly identified candidate; (2) require communications paid for and authorized by a candidate, and communications paid for by other persons but authorized by a candidate, to include a clearly readable statement identifying the candidate and stating that he or she has approved the communication; (3) require such communications transmitted through the Internet to meet applicable requirements with respect to any audio and video portions; (4) subject to disclosure requirements campaign communications made through prerecorded telephone calls; and (5) provide for the treatment as audio communications of prerecorded telephone calls, thereby subjecting them to applicable requirements pertaining to communications transmitted through radio.