Biden’s O.C.C. pick declares her support for capitalism and community banks.

When she faces a room full of United States senators — some of whom have suggested she is a communist — Saule Omarova, President Biden’s pick to lead the Office of the Comptroller of the Currency, will introduce herself by declaring that she loves two things: American capitalism and community banks.

Ms. Omarova, a Cornell Law School professor, sets out Thursday on a tough path to confirmation as the head of the regulator overseeing national banks. Soon after her nomination, bank lobbyists began an unusually strident campaign against her, echoing critics who cited her birthplace — Kazakhstan, a former Soviet republic — as a reason to question her loyalty to the United States.

Bankers claimed that her academic writing proved that she was poised to replace the banking system with a government-run alternative. Even members of the Senate Banking Committee, where Ms. Omarova is set to appear, joined in questioning her views: The committee’s highest-ranking Republican, Pat Toomey of Pennsylvania, repeatedly demanded to see Ms. Omarova’s master’s thesis to check it for Marxist ideas.

In a prepared opening statement posted on the Senate Banking Committee website on Wednesday, Ms. Omarova cast her background in the opposite light. She grew up, she said, with a grandmother who was orphaned when Stalin sent her family to Siberia for refusing to join the Communist Party.

She described the government during her childhood as an “oppressive state-run system, with no free enterprise and no economic opportunity for people like me.” Her ultimate dream, she said, became “coming to America — the land of opportunity and freedom.”

Ms. Omarova also vowed to “guarantee a fair and competitive market where small and midsize banks that invest in their neighbors’ homes and small businesses can thrive.” She added that her mission would include “preserving and fostering the relationship banking that drives economic growth and creates local jobs and prosperity.” Twice in the remarks, Ms. Omarova pointed out that she had worked for a Republican president, George W. Bush.

If confirmed, Ms. Omarova would lead the regulator that banks are looking to for clarity on how they can participate in cryptocurrency markets, as well as how they can more successfully compete with nonbank financial technology companies, or fintechs. She would most likely have to design new rules for the decades-old anti-redlining law, the Community Reinvestment Act, and would be expected to help carry out Mr. Biden’s stated mission to get the financial industry to help combat economic inequality and climate change.

Thursday’s hearing is only the first of several hurdles Ms. Omarova must clear. The committee will later vote on her nomination, and if it is approved there, it would face a full Senate vote.