Raj Date, a top deputy to Elizabeth Warren at the Consumer Financial Protection Bureau, will take over day-to-day operations of the new watchdog agency when she departs at the end of this month, Treasury officials announced Tuesday.

Warren has served since September overseeing the creation of the bureau, which officially opened its doors last week. She hired scores of staffers, met with bankers and lawmakers across the country, and defended the agency to a skeptical financial industry and Republicans on Capitol Hill.

In the process, Warren became a political lightning rod. She had hoped to stay on as the bureau’s inaugural director, and undoubtedly was the first choice of most consumer advocates. Nevertheless, President Obama last week instead nominated Richard Cordray, a former Ohio attorney general who this year became chief of the CFPB’s enforcement division.

While Cordray waits for a Senate confirmation that might be a long time coming — Republicans have vowed to block any nominee unless Obama agrees to fundamental changes in the bureau’s structure, including wanting the bureau led by a five-member commission rather than a single independent director — Date will assume Warren’s current role.

Date joined the bureau in February as associate director of research, markets and regulations, overseeing its work on key issues such as credit cards and mortgages. Previously, he spent years working at Capital One and Deustche Bank. He left the banking industry in 2009 to start a nonprofit think tank devoted to promoting the regulation of financial firms. When Warren hired him, she cited his ability to keep the CFPB at “the cutting edge” of the financial industry.

“Professor Warren has done an extraordinary job standing up the Consumer Financial Protection Bureau,” Treasury Secretary Timothy F. Geithner said in a statement. “Her efforts to simplify mortgage and credit card disclosures, protect military families from abusive and deceptive financial practices, and bring aboard top talent like Richard Cordray and Raj Date have built a strong foundation for the bureau’s future success.”

Warren plans to return to Cambridge, Mass., and resume her position as a professor at Harvard Law School this fall. But that doesn’t necessarily mean she is finished with Washington. Many liberal groups have urged Warren to challenge Sen. Scott Brown (R-Mass.) next year, going as far as to circulate petitions and even begin fundraising for a possible run.