WASHINGTON  President Obama plans to continue reshaping his inner circle on Friday, replacing his brusque and aggressive chief of staff, Rahm Emanuel, with a soft-spoken insider who has worked quietly in Mr. Obama’s shadow for years.

Pete Rouse, a senior adviser to Mr. Obama who has little public profile but considerable influence in the West Wing, will become the president’s new gatekeeper, at least through the election in November, as Mr. Emanuel moves back to Chicago to run for mayor, officials said.

Senior aides to Mr. Obama described Mr. Rouse as a temporary pick, but one who is likely to stay for several months and may in the end turn out to be the president’s final choice. Mr. Rouse has expressed reservations about holding the job for an extended period.

The decision to tap Mr. Rouse reflects a desire by the president to maintain his small circle of close advisers for now rather than bringing in an outsider or elder statesman to present a new face as Mr. Obama heads into the second half of his term with his popularity down and his party facing the possibility of big losses in November. Known as a fixer inside the White House, Mr. Rouse has had a largely unseen hand in most of the president’s big policy decisions of the last 20 months.