Senator Charles E. Schumer of New York, long admired, and reviled, for his uncanny ability to make it all about Chuck, has worked his way into the party?s No. 3 job in the Senate, where he puts his promotional talents to work on behalf of all his Democratic colleagues.

With his party still trying to regain its footing after big Republican gains in November, and with many of his fellow Democrats already worried about holding on to their seats in 2012, he has been given responsibility for sharpening the Democratic message from Capitol Hill and marrying it more effectively to the policies the party is trying to advance.

?Usually, things change when you don?t do so well,? Mr. Schumer said. ?My job, our job as a caucus, is to focus on the average family, to show them we actually care about them.?

This will be accomplished, he contends, through the three P?s: ?policy, politics and press.?

But leading a disparate group of Senate Democrats ? a group at war with the emboldened House Republicans and in search of cover from the White House ? is proving a challenge.

Mr. Schumer must weigh the hopes and dreams of his most liberal members, who crave open ideological battle with Republicans, while watching the backs of moderates, who are pushing for their own deficit-reduction narrative.

?Getting everyone in the tent is hard,? said Senator Claire McCaskill, Democrat of Missouri. ?Getting everyone to speak with one voice is near impossible.?

What is more, Mr. Schumer?s attempt to verbally smack around Republicans has frequently been cold-shouldered by the White House, where President Obama has been repositioning himself more toward the political center and shying away from inflaming the budget fight. White House aides have more often than not tossed sheets of ice on the fairly enormous hill that Mr. Schumer climbs in leading his caucus forward.

The Democrats are clear that they want fewer cuts to discretionary spending than Republicans are demanding, but they have yet to settle on what level of reductions they would accept. There are rifts within the party over taxes, addressing the long-term costs of Medicare, Medicaid and Social Security, reining in agricultural subsidies and scaling back the war in Afghanistan.

?They seem to be pushing different agendas,? said Representative Henry A. Waxman, Democrat of California. ?I think they are getting ahead of themselves.?

When House Republicans offered up a short-term spending plan a few weeks ago, the press office run by Mr. Schumer and the majority leader, Senator Harry Reid of Nevada, rejected it out of hand, even though it largely mirrored White House ideas. Then the Senate quickly passed it, leaving the initial messaging looking more reflexive than considered, more defense than offense ? and defense is not the game Mr. Schumer best likes to play.

Mr. Schumer?s difficulties were foretold in December, days after he assumed his new post. As the House and Senate fought over the preservation of the Bush-era tax cuts on upper-income levels, Mr. Schumer pushed for a tax that would extend only to millionaires; the proposal fell flat, with the White House failing to support it.

Fast-forward to last Wednesday. Mr. Schumer gave a high-profile speech insisting that cuts to entitlement programs and tax increases be part of the spending bill discussion; hours later, a White House spokesman said that would not be happening. Mr. Schumer concedes that their paths diverge, but brushes off the idea that this is suboptimal. ?As long as we communicate,? he said, ?everything will work out.?

Over the last 72 hours, Mr. Schumer has shown up at news conferences and events to push the notion that House Republicans are pushing the federal budget off the rails. There he was Sunday on NBC?s ?Meet the Press? saying that Republicans will not compromise. On Monday, between zipping around New York, he issued a news release intended to fan the flames of that argument.

Tuesday morning he was on a conference call with Senator Debbie Stabenow, Democrat of Michigan ? one of Mr. Schumer?s four public events ? ostensibly to talk about China?s hoarding of rare earth elements, but also attacking House conservatives for trying to attach policy initiatives to the short-term spending plan. ?The conservative Republicans in the House are showing themselves to be the Scott Walker Republicans,? Mr. Schumer said, referring to the governor of Wisconsin. They are trying to ?shoot for the moon on a wish list of far-right policy measures.?

For many Senate Democrats, Mr. Schumer?s new role has been a great gift for a group still smarting from missteps that dinged the body?s reputation in recent years.

Last year, at a Democratic retreat, junior senators, led by Al Franken of Minnesota, lit into Mr. Reid and the White House about being left out of policy and strategy discussions, even though they helped secure the party?s majority.

?I?ve really appreciated how he?s made our decision-making process much more participatory,? Mr. Franken said of Mr. Schumer in an e-mail. ?Knowing that our primary focus is on how our work here affects our constituents back home, he also has made a noticeable effort to ensure that we have clear information on how each policy affects our state specifically.?