This study introduces a novel approach to enhancing the sensitivity of microwave sensors by employing electric-LC (ELC) resonators. The sensor design features a microstrip line capacitively coupled to an ELC resonator, which incorporates an interdigital capacitor (IDC) to intensify the electric field, thereby improving the measurement of material characterization. An ELC resonator, also known as a cascaded resonator, further boosts sensitivity and enhances the accuracy of dielectric measurements. We designed the sensor on a low-loss Taconic TLY-5 substrate with a loss tangent of 0.0009 and a dielectric constant of 2.2. It operates in the S-band (2–4 GHz) at 3.11 GHz. Simulations using CST Microwave Studio, conducted on materials with permittivity values ranging from 2 to 10, revealed a normalized sensitivity of 5.76%, corresponding to a frequency shift of 179.3 MHz, which exceeds previously reported values in the literature.