President Barack Obama plans an intense but largely behind-the-scenes effort on health care reform legislation this week as the White House scrambles to help Senate Majority Leader Harry Reid (D-Nev.) push the bill toward passage.

White House officials scoff at the idea that Obama is not aggressively involved in lobbying for the bill. Some outside the White House have suggested Obama is playing a passive role since he dialed back his public campaign for the measure late last summer.

“We wouldn’t be sitting here the 14th of December, when you’d much rather be Christmas shopping, discussing the Senate being in on the weekends if the president wasn’t involved,— White House Press Secretary Robert Gibbs said. “The president’s been involved the whole time,— he added.

Obama “will continue to be fully engaged,— said another senior White House official.

The president today is bringing the entire Senate Democratic Conference to the White House to rally them to pass the legislation.

Obama may bring more Senators to the White House to meet with him individually as the week wears on, aides said. But they declined to specify who might get an invite, noting such sessions are generally put together at the last minute as Obama and his aides decide who needs a little encouragement.

The president will also be working the phones, as aides say he has done all through the process.

White House advisers pointedly noted that Obama will be talking to Republicans as well as Democrats, an indication that he has not given up on persuading Sen. Olympia Snowe (Maine) and possibly a few other GOP moderates to back the bill.

But officials say no speeches or public events on health care are planned for this week.

The president for weeks has been avoiding the type of rallies and interviews — marked by a blitz of the Sunday talk shows in September — that characterized the spring and summer.

Even the weekly radio address, which for several weeks running focused on health care, is now frequently devoted to other topics, such as Afghanistan, the economy and financial reform.

Obama in recent weeks has kept his public focus on Afghanistan and the economy. Instead of publicly touting health care, he has made statement after statement seeking to rebut Republican arguments that his economic policies are a failure as the recovering economy fails to create many new jobs.

Gibbs said Obama was eschewing public events on the health care issue in order to spend more time “discussing things with those who are going to vote.—

Meanwhile, White House Chief of Staff Rahm Emanuel continues to lead the staff lobbying effort on behalf of the bill. Also continuing to play key roles are Legislative Affairs Director Phil Schiliro, Office of Management and Budget Director Peter Orszag, White House “health czar— Nancy-Ann DeParle, and White House Deputy Chief of Staff Jim Messina.

White House officials describe Messina and DeParle as practically living on Capitol Hill.

Obama aides view Messina as well-positioned to help lead the charge. Messina was chief of staff to Sen. Max Baucus (D-Mont.) — who crafted large parts of the health care bill — and Sen. Byron Dorgan (D-N.D.), and he knows the Senate and its Members intimately.

But Messina is also a political operative, having served not only at the top levels of the Obama campaign but as campaign manager for Baucus during his 2002 re-election effort.

The experience makes Messina particularly sensitive to the political considerations of Senators from relatively conservative states — like Montana — who must potentially cast votes that will anger moderates and conservatives in their states.

Vice President Joseph Biden also continues to be in contact with his former Senate colleagues on health care.

Biden earlier this fall held a meeting at the White House with Sen. Joe Lieberman (ID-Conn.), one of the key swing votes on the bill. Obama has not met one-on-one with Lieberman at the White House so far.