A key Senate committee on Tuesday approved President Donald Trump's choice to lead the Department of Homeland Security.

The Senate Homeland Security and Government Affairs Committee approved Kirstjen Nielsen's nomination, 11-4. The panel's chairman, Sen. Ron Johnson, R-Wis., said the full Senate could vote on Nielsen's nomination by the end of November.

Nielsen, 45, is a former staffer at DHS who now serves as deputy White House chief of staff.

Democrats complained that she lacked the experience needed to run a major agency with 240,000 employees. They also cited concerns about possible White House interference in a recent DHS decision to send home thousands of Nicaraguans long granted U.S. protection.

Johnson dismissed those concerns and said Nielsen's boss, White House chief of staff John Kelly, has called her a "superstar."

The Homeland Security post "is a very big job. Probably no one is fully qualified for it. I think she has some good qualifications," Johnson said, adding that it was important to fill the post as soon as possible.

Sen. Kamala Harris, D-Calif., said Nielsen has played a role in several questionable Trump administration decisions, including several attempts at a travel ban to restrict entry from selected countries, termination of a program for young immigrants and what Harris called a "feeble response to Hurricanes Irma, Maria and Harvey."

Harris also said she was troubled by Nielsen's failure to acknowledge at her confirmation hearing how human behavior contributes to climate change.