CMGI, INC.

LIMITED POWER OF ATTORNEY


	This statement confirms that the undersigned has authorized and
designated Peter L. Gray, Kevin P. Lanouette and Thomas B. Rosedale his
attorneys-in-fact to (i) prepare, execute and file on behalf of the
undersigned Form ID in order to obtain access codes for the undersigned
to permit filing on EDGAR, and (ii) prepare, execute and file on behalf
of the undersigned all Forms 3, 4 and 5 (including any amendments thereto)
that the undersigned may be required to file with the U.S. Securities and
Exchange Commission as a result of the undersigned's ownership of or
transactions in securities of CMGI, Inc.  The authority of such attorneys
under this Power of Attorney shall continue until the undersigned is no
longer required to file Forms 3, 4 and 5 with regard to the undersigned's
ownership of or transactions in securities of CMGI, Inc., unless earlier
revoked in writing.  The undersigned acknowledges that such attorneys are
not assuming any of the undersigned's responsibilities to comply with the
requirements of Section 16 of the Securities Exchange Act of 1934, as
amended, or any of the undersigned's liabilities for failure to comply
with such requirements.


Date: February 2, 2005			/s/ William R. McLennan
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						William R. McLennan