We present a search for the technicolor particles ρT and πT in the process pp→ρT→WπT at a center of mass energy of s√=1.96  TeV. The search uses a data sample corresponding to approximately 1.9  fb−1 of integrated luminosity accumulated by the CDF II detector at the Fermilab Tevatron. The event signature we consider is W→ℓν and πT→bb, bc or bu depending on the πT charge. We select events with a single high-pT electron or muon, large missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with multiple b-tagging algorithms. The observed number of events and the invariant mass distributions are consistent with the standard model background expectations, and we exclude a region at 95% confidence level in the ρT-πT mass plane. As a result, a large fraction of the region m(ρT)=180–250  GeV/c2 and m(πT)=95–145  GeV/c2 is excluded.