Inclusion Criteria:  Age ≥ 18 years. Confirmed diagnosis of de novo Glioblastoma (WHO Grade IV glioma) by histopathology or molecular studies. (Secondary GBM not eligible). The tumor must have a supratentorial component. Patient have completed standard external beam radiation with concomitant temozolomide.  (Minimum dose for concomitant radiotherapy is 40 Gy)  Patient must be receiving adjuvant therapy with Temozolomide at time of enrollment. Karnofsky Performance Status (KPS) ≥ 70. Signed informed consent. If the patient's mental status precludes his/her giving informed consent, written informed consent may be given by the legally authorized representative. For females of childbearing potential, negative serum pregnancy test at enrollment. Women of childbearing potential (WOCBP) must be willing to use acceptable contraceptive method to avoid pregnancy throughout the study and for at least 24 weeks after the last dose of study drug.  Refer to Appendix B for definition of WOCBP and guidance on acceptable contraceptive methods.  -Males with female partners of childbearing potential must agree to practice adequate contraceptive methods throughout the study and should avoid conceiving children for 24 weeks following the last dose of study drug.  Refer to Appendix B for guidance on acceptable contraceptive methods.  For patients receiving steroids, daily dose must be < 4 mg.  Adequate Bone marrow and organ function as defined below:  Absolute neutrophil count (ANC) ≥ 1,500 cells/mm3. Platelet count ≥ 100,000 cells/mm3. Hemoglobin ≥ 9 g/dl. (The use of transfusion or other intervention to achieve Hgb ≥ 9 g/dl is acceptable.) BUN ≤ 25 mg/dl Creatinine ≤ 1.7 mg/dl Bilirubin ≤ 2.0 mg/dl ALT ≤ 5 times institutional upper limits of normal for age AST ≤ 5 times institutional upper limits of normal for age  Exclusion Criteria:  Prior invasive malignancy (except for non-melanomatous skin cancer) unless disease free for ≥ 3 years. Metastases detected below the tentorium or beyond the cranial vault and leptomeningeal involvement. Recurrent disease Multifocal gliomas defined as distinct tumors that do not have overlapping T2/FLAIR signal. HIV, Hepatitis B, or Hepatitis C seropositive. Known active infection (requiring treatment by antiviral or antibiotic) at time of enrollment Immunosuppressive disease.  Severe, active co-morbidity, defined as follows:  Unstable angina and/or congestive heart failure requiring hospitalization. Transmural myocardial infarction within the last 6 months. Chronic Obstructive Pulmonary Disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy at initiation of XRT/TMZ. Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects. Acquired Immune Deficiency Syndrome (AIDS) based upon current CDC definition. The need to exclude patients with AIDS from this protocol is necessary because the treatments involved in this protocol may be significantly immunosuppressive. Patients with autoimmune disease requiring medical management with systemic immunosuppressants. Major medical illnesses or psychiatric impairments that, in the investigator's opinion, will prevent administration or completion of protocol therapy. Pregnant or lactating women, due to possible adverse effects on the developing fetus or infant. Women of childbearing potential and men who are sexually active and are unwilling or unable to use an acceptable method of contraception for the entire study; this exclusion is necessary because the treatment involved in this study may be significantly teratogenic. Prior allergic reaction to TMZ, GM-CSF, or Td. Patients who have received an investigational agent within 28 days prior to study entry.