EXHIBIT 32.1


                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                       AS ADOPTED PURSUANT TO SECTION 906
                        OF THE SARBANES-OXLEY ACT OF 2002

                  In connection with the Quarterly Report of CenterPoint Energy
Resources Corp. (the "Company") on Form 10-Q for the period ended March 31, 2005
(the "Report"), as filed with the Securities and Exchange Commission on the date
hereof, I, David M. McClanahan, Chief Executive Officer, certify, pursuant to 18
U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley
Act of 2002, to the best of my knowledge, that:

                  1. The Report fully complies with the requirements of section
13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

                  2. The information contained in the Report fairly presents, in
all material respects, the financial condition and results of operations of the
Company.

         /s/ David M. McClanahan
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David M. McClanahan
President and Chief Executive Officer
May 11, 2005