WASHINGTON: US President Barack Obama turned to low-key insider Pete Rouse Friday to replace high-profile chief of staff Rahm Emanuel in a prelude to a wider staff shake-up expected at the White House. Obama named Rouse, a veteran Capitol Hill operator, to take over at least on an interim basis from Emanuel, 50, who announced his resignation as Obama's top aide to launch a campaign for Chicago mayor. More turnover is expected with the Nov. 2 congressional elections presenting a traditional period for aides, exhausted from long days over the past two years, to move on. Obama is likely to face a more hostile US Congress next year with Republican gains expected in the elections, and that could be a factor in how he reshapes his team. The changes could signal a fresh start as he tries to boost his weak poll numbers and prepare for his 2012 re-election campaign. Rouse, 64, is one of Obama's longest-serving aides, working for him since Obama was a US senator from Illinois. He was previously chief of staff to Democrat Tom Daschle when he was a senator, so influential that he was sometimes called “the 101st senator.”