This paper introduces a novel method using campaign finance data to measure political ideology.

Measurement Approach: By analyzing over 100 million contribution records from state and federal elections, ideal points for diverse actors are estimated. The common pool of contributors allows for unified ideological measures across different institutions.

Who We Measure: The approach captures ideology not just for incumbents but also candidates regardless of their status, including members of Congress, the president's executive branch, state legislators, governors, and other officials.

Key Features & Findings:

• Ideology measured through contribution patterns
• Covers federal, state, and local levels
• Includes interest groups and individuals as donors
• Addresses validity concerns and strategic behavior issues

What This Means: This methodology opens up new avenues for political science research by enabling comparative analysis of ideology across all these actors simultaneously.