Columbia subject headings:
Legislators--United States.
Polarization (Social sciences)--United States--21st century.
Political parties--United States--21st century.
United States. Congress--Elections.
Harvard subject headings:
Princeton subject headings:
Divided government--United States--21st century.
Legislators--United States--21st century.
Party affiliation--United States--21st century.
Polarization (Social sciences)--United States--21st century.
Political parties--United States--21st century.
United States. Congress--Elections--21st century.