Elena Shao in the New York Times:

When the current Congress was convened in January, there were nearly 120 members who were 70 or older — 86 in the House, including nonvoting delegates, and 33 in the Senate. This number, which is unmatched in modern history, included 14 octogenarians in the House, five in the Senate, and 91-year-old Senator Charles E. Grassley, Republican of Iowa.

Seniority and longevity have long been rewarded, both at the polls and internally within the two major parties. Even so, some of the country’s oldest lawmakers have faced scrutiny in recent years over age and fitness to serve after very public episodes of what looked to be disorientation or decline.