Senate GOP Weighs Whether to Pick a Tax Writer as Next Leader

Visitors to Sen. John Cornyn’s office are greeted with a portrait not of the Texas Republican but of the Finance Committee, with Cornyn in the front row. In the back row, South Dakota Republican John Thune towers over his colleagues.

The picture highlights the importance of the Senate Finance Committee, among the most powerful in Congress and set to play a key role as lawmakers address next year’s expiration of trillions of dollars of tax cuts.

Current Senate Minority Whip Thune and Cornyn, a former whip and former National Republican Senatorial Committee chair, are front-runners to become the next Senate ...