PORTLAND, Me.

First through the door of the Portland Community Health Center on Thursday morning was a stick figure of a man, oblivious to the homemade signs and the White House advance team across the street. He had a bald eagle drawn on his sweatshirt, a street-hard weariness in his eyes, and a throbbing pain in his right hand.

Sarah Andel, a nurse practitioner, knew this man, James Hierl: how he lived in a shelter; how his depression made eating seem futile. As she held his numbed hand, working to remove a painful wart with a blade, she coaxed and coddled him: You have to eat; you have to see your psychiatrist; and please, James, eat.

“You’re going to come back in a week,” Ms. Andel said, as her patient headed for the door, finger bandaged, cheeks concave, looking older than his 53 years. “O.K., James?”

Mr. Hierl gave a hesitant nod. Soon he was out on Park Avenue, where a line was forming outside a brick bandbox called the Portland Expo. The reason: President Obama was to speak there in the afternoon about new health care legislation that, among other things, will provide a huge increase in money — $11 billion — to community health centers like this one.