Chuck Grassley

Charles Ernest "Chuck" Grassley (born September 17, 1933) is the senior U.S. Senator from Iowa. He was the 91st Senate President pro tempore from 2019 until 2021. He has been Senator since 1981. He was also in the United States House of Representatives from 1975 to 1981. Before that he was in the Iowa state legislature from 1959 to 1974.
In January 2019, Grassley became the most senior Republican serving in the United States Senate due to the retirement of Orrin Hatch and the resignation of Thad Cochran. After the Republicans kept control of the Senate in the 2018 elections, Grassley became the 91st Senate President pro tempore.
In January 2021, when Republicans lost control of the U.S. Senate, Patrick Leahy became President pro tempore while Grassley became "President pro tempore emeritus".
On November 17, 2020, Grassley announced that he had tested positive for COVID-19.
In January 2023, withy Patrick Leahy's retirement, Grassley became the Dean of the United States Senate.