The potential 2028 presidential candidates showcased a Democratic midterm strategy that would assail G.O.P. votes in favor of cutting Medicaid and allowing health care subsidies to expire.
Pete Buttigieg argued that pressure from Wisconsinites had led their Republican congressional representative to vote in support of extending enhanced health care subsidies.
As the F.B.I. has added payback to its portfolio, Republican lawmakers like Senator Charles E. Grassley have emerged as a clearinghouse for leaks and whistle-blowers.
Under Kash Patel, F.B.I. personnel have worked to paint a damning, one-sided narrative intended to discredit and embarrass federal law enforcement officials who investigated Donald J. Trump and his allies.
The president urged Representative Julia Letlow of Louisiana to run against Mr. Cassidy, in a move that is likely to further complicate his relationship with Senate Republicans.