Rep. Paul Hodes was feeling pretty good until he bumped into Rep. Rahm Emanuel in the back of the House chamber.

Hodes (D-N.H.) was upbeat because his staff had helped return the dog of a soldier slain in Iraq to his family.

The message, delivered in Emanuel’s characteristic blunt Chicago manner, was that members shouldn’t get complacent. Usually those messages were sprinkled liberally with four-letter words, particularly one that begins with “F.”

And that’s why Emanuel’s friends and adversaries all say his departure to be White House chief of staff will fundamentally alter how the Democratic House majority will be run. Emanuel’s job as caucus chairman will be assumed by Rep. John Larson (D-Conn.), but his role as resident bad cop will go unfilled.

Emanuel, known to friends and enemies simply as “Rahm,” played several pivotal roles in the Democratic leadership. And most of them would not ordinarily be listed on the job description for caucus chairman.

He was simultaneously the gruff coach and loyal protector of the 42 freshmen he brought to Congress as the House campaign chief in 2006. He was an enforcer of party discipline and sometimes even acted like the whip, lining up votes on the floor. A former investment banker, he brought financial experience and business-minded ideas. And behind closed doors, he was the one who prodded the House leadership toward decisions. Sometimes he shoved.

And, leadership aides said, sometimes that meant directing that unique frankness to House Speaker Nancy Pelosi (D-Calif.).

“If she’s in a holding pattern, there’s very little staff can do to move her,” said a Democratic aide. “His role was to bring her over the top.”

No one in the current leadership has that mixture of talents. And likely no one has the standing to speak so bluntly to Pelosi.

Even some of those who chafed at Emanuel’s style are excited to have a House insider next door to the Oval Office.

But his departure also raises the possibility that the incoming freshmen from conservative districts aren’t shielded from tough votes, that business viewpoints aren’t heard in the leadership suites where many bills are written and that key decisions are kicked down the road by the leadership.

Some members say they’re not worried.

“The skills needed to efficiently run this caucus are present,” Hodes said. “It’s important to see we are working toward bipartisanship. This leadership team is better positioned to deal with the current reality.”

The amiable, diplomatic Larson, the caucus vice chairman, presents a stark contrast to Emanuel’s brusque, impatient manner.

“They’re polar opposites,” said Rep. Jason Altmire (D-Pa.).

Altmire, a freshman returning from a conservative district, said he is among those who worry that Emanuel’s centrist voice will be lost.

“When I talked to Larson, I told him I was concerned about a move to the left,” Altmire said. “Leadership gets the danger that exists. It remains to be seen how this group interacts.”