The Washington Post takes a look today at the White House's efforts to maintain unity in a diverse Democratic caucus.

This anecdote on Obama's lobbying efforts for Waxman-Markey stood out:
When Obama entered the fray on May 5, summoning all 36 committee Democrats to the White House, he didn't make a single demand. Rather, participants say, he pointed to a portrait of Abraham Lincoln and said, "He had a chance to affect history. You, too, have a chance to affect history."

As a junior Democratic lawmaker, it'd be pretty hard to refuse Obama after that.

The more systematic effort, however, is outreach to politically vulnerable first- and second-term Democrats. The White House is making every effort to extend the perks of the executive branch to keeping those members happy.
Rep. Jason Altmire, elected in 2006, was invited to a breakfast in March with Veterans Affairs Secretary Eric K. Shinseki to discuss issues related to the large population of veterans in Altmire's western Pennsylvania district. Altmire's office and the VA now communicate regularly. Maffei was given a leading role in pressing two popular bills, to curb credit card practices deemed harmful to consumers and to protect auto dealers.

Rep. Ed Perlmutter (D-Colo.), a member of the class of '06, said he has had extensive discussions with top administration officials on financial regulatory reform, another Obama priority. When he expressed to a White House official his interest in talking with Housing Secretary Shaun DonovanShaun L. S. DonovanHouse Dems call on OMB to analyze Senate budget plan Overnight Finance: Dems turn up heat on Wells Fargo | New rules for prepaid cards | Justices dig into insider trading law GOP reps warn Obama against quickly finalizing tax rules MORE about a piece of legislation, he got a call the next day setting the meeting for three days later. He has met with three other Cabinet officials to discuss bills.

But it doesn't always work. "I'm a firm no," told Rahm Emanuel just before the Waxman-Markey vote. "I wouldn't waste any more time talking to me."