We report the results of a search for a narrow resonance in electron-positron events in the invariant mass range of 150–950  GeV/c2 using 1.3  fb−1 of pp collision data at s√=1.96  TeV collected by the CDF II detector at Fermilab. No significant evidence of such a resonance is observed and we interpret the results to exclude the standard-model-like Z′ with a mass below 923  GeV/c2 and the Randall-Sundrum graviton with a mass below 807  GeV/c2 for k/Mpl=0.1, both at the 95% confidence level. Combining with diphoton data excludes the Randall-Sundrum graviton for masses below 889  GeV/c2 for k/Mpl=0.1.