Stretchable electronics are becoming popular due to their high adaptability to various environments and durability against external forces. We propose a method of designing and fabricating stretchable electronics using a multi-material conductive elastomer structure embedded with silver (Ag) powders and carbon nanotubes (CNTs). While the Ag-based polymer is used for highly conductive electrical connections, such as electrodes and signal wires, the CNTs-based polymer can be formed to be electrical components, such as resistors and sensors, due to the relatively high resistivity. Stretchable electronics composed of different types of conductive polymers have several advantages, such as noise reduction by separating signal wires from sensing components, target-specific sensing with free wire routing, and construction of fully stretchable electronics with various passive elements. In this paper, we describe the design and the fabrication of the proposed stretchable electronics with experimental characterization on the performance. We also demonstrate applications that take advantage of the proposed method, including a wearable strain sensor, an array of soft strain gauges with a rosette configuration, and a fully stretchable circuit composed of soft components, such as resistors, capacitors, and inductors. All the application devices are fabricated only by simple laser cutting.