Do politicians fulfil election pledges during campaigns and transform them into subsequent actions once in office? While previous research generally finds congruence between election pledges and policymaking activities in legislatures at the political party level, we know less about the relationship between campaign pledges and legislative priorities on the level of legislators. Analyzing Japanese candidate manifestos offers a unique opportunity to study whether issue emphasis in campaign communication serves as a meaningful signal of legislative activities. First, using supervised machine learning, we identify issue emphasis in over 56,000 sentences from over 1,000 manifestos by Japanese Members of Parliament between 2003 and 2017. Candidates with higher manifesto salience of a policy area are significantly and substantively more likely to take leadership positions in the Diet committees, the Cabinet, and the party in the same policy area. In addition, we find that such congruence is stronger for less important policy areas. Our findings suggest that campaign promises provide meaningful signals of subsequent legislative behavior.