Mr. Emanuel oversees two working groups: a policy group, run by Nancy-Ann DeParle, the head of the White House Office of Health Reform, and a political group, run by Jim Messina, the deputy chief of staff. They are deeply engaged in what Chris Jennings, who advised President Bill Clinton on health policy, calls “intelligence seeking” — trying to learn who has problems with the legislation, what those problems are and what it will take to win each member’s vote.  “We are at the concern-addressing stage,” said Dan Pfeiffer, Mr. Obama’s deputy communications director, adding, “This is a political and policy challenge of epic proportions, and it takes a lot of effort and attention to achieve it.”  Everyone who has relationships on Capitol Hill is expected to pitch in. Mr. Messina, a former chief of staff to Senator Max Baucus of Montana, the Finance Committee chairman, is the link to the finance panel. Phil Schiliro, the head of legislative affairs, spent years working for Representative Henry A. Waxman, the California Democrat who is an architect of the House bill. Vice President Joseph R. Biden Jr., who served for 36 years in the Senate, has been making calls to former colleagues, especially those on the Finance Committee.  Kathleen Sebelius, the secretary of health and human services, Tom Vilsack, the agriculture secretary, and Gary Locke, the commerce secretary, have also been working the phones. Their notes are passed on to Mr. Schiliro’s shop, which catalogs them for future use. The cabinet secretaries have also been doing interviews with select regional news outlets to shore up wavering Democrats in districts where Republicans are attacking Mr. Obama’s plans.  And the president has been holding more private meetings, aides say, with Democrats like Senator Maria Cantwell of Washington, who said she received an invitation to the Oval Office on a recent Friday, when she had hoped to spend the morning at home. She said she told the president the legislation would have to do more to rein in Medicare spending. “He was, like, ‘I’m all for this,’ ” Ms. Cantwell said.  “He is leaving no stone unturned,” said Senator Mary L. Landrieu, the Louisiana Democrat and Appropriations Committee member, who received an unsolicited call from Ms. Sebelius last week. She said they spent 20 minutes going over what she perceived as flaws in the bill.  The White House is carefully monitoring what senators say. When Senator Joseph I. Lieberman, the Connecticut independent, said on a Sunday morning talk show that health legislation should be delayed until the economy improves, his chief of staff got a telephone call from a worried-sounding Louisa Terrell, the White House legislative liaison assigned to monitor his office.  “She said, ‘Does he want to speak to Sebelius, does he want Peter Orszag?’ ” the senator said. He said it was not necessary. But last Friday, while Mr. Lieberman was at home preparing for Rosh Hashana, Mr. Locke, the commerce secretary, called. “He wanted to lobby me on health care,” Mr. Lieberman said.  At least one White House official, Ms. DeParle, has gone so far as to make a house call. When Senator Dianne Feinstein, Democrat of California, expressed misgivings about how expanding Medicaid would affect California’s budget, Ms. DeParle gathered some charts and dropped in on a Saturday. They spent nearly three hours talking over coffee in Ms. Feinstein’s den.  Republicans who have been most outspoken about their opposition to the White House say they have been left out of the outreach effort, and some are irked. “The strategy seems to be like a shooting gallery at the state fair; if you hit one target, you win the prize,” said Senator Lamar Alexander of Tennessee, chairman of the Republican conference.  By “one target,” he meant Ms. Collins’s colleague from Maine, Senator Olympia J. Snowe, who serves on the Finance Committee and is considered Mr. Obama’s sole hope for a Republican vote there. Ms. Collins, who does not sit on the committee, has made clear that she would not get in Ms. Snowe’s way by stating a position before Ms. Snowe does. But that has not stopped the White House from working hard behind the scenes to secure her support.  Two days after Mr. Obama addressed a joint session of Congress, Mr. Emanuel invited Ms. Collins to meet with him in the West Wing — and conveniently arranged for the president to drop in. When that failed to produce a commitment, Mr. Emanuel urged Mr. Orszag to step in. Ms. Collins is not surprised by the attention.  “This is clearly a high priority for the president, and he is deploying all of his troops to try to persuade people like me who thus far are not happy with any of the bills,” she said. She came away from the dinner sounding impressed — “Peter is very expert,” she said — but remained noncommittal. And lest there be any suspicions that her vote can be had for the price of a lamb chop, the senator was emphatic.  “We split the bill,” she said.  An article last Sunday about the Obama administration’s efforts to round up votes for proposed health care legislation erroneously included one senator as a member of the Senate Finance Committee, which is currently considering the legislation. While Senator Mary L. Landrieu, Democrat of Louisiana, is on the Senate Appropriations Committee, among others, she is not on the Finance Committee.  A version of this article appears in print on September 27, 2009, on Page A16 of the New York edition with the headline: Taking Health Care Courtship Up Another Notch. Order Reprints| Today's Paper|Subscribe
White House officials say they have begun an aggressive campaign to line up votes for a health care bill.