Sen. Chuck Schumer (D-N.Y.), a member of the Joint Congressional Committee on Inaugural Ceremonies, looks out over the National Mall from the U.S. Capitol the day before President Obama’s second inauguration. (Jim Lo Scalzo/EPA)

Even for Chuck Schumer, this has been a month of high visibility. As the master of ceremonies for President Obama’s second inauguration, the senior senator from New York introduced the president’s address with a rabbinical cadence that evoked, for “The Daily Show’s” Jon Stewart, “post-Shabbat service announcements.” Schumer also presided over the luncheon at Statuary Hall in the Capitol with jazz hands and toasts. (“Slainte. L’chaim. Salud. Cent’anni.”) He concluded by directing attendees to the next event: “It’s now time to head to our next happy stop — the presidential parade.”

Casual viewers who tuned in to watch the festivities could have been forgiven for mistaking Schumer for the president’s Borscht Belt footman.

Actually, he’s become the president’s right-hand man on Capitol Hill.

That’s a remarkable development.

During Obama’s first term, Schumer groaned about the president’s naivete in espousing post-partisan “come together” platitudes. He anguished over the president’s tendency to cave in to Republicans. He bemoaned the president’s decision to push for health-care reform before ensuring that the economy was on a solid footing. He wanted to crush the opposition, not compromise.

On Inauguration Day, though, the senator looked pleased by the president’s pronouncement of an assertive and almost Schumeresque progressive agenda. The man who publicly took the oath of office Jan. 21 had learned many of the hard political lessons that Schumer already knew in January 2009, when Obama was sworn in for the first time.

But Schumer, too, has taken a new direction. At a time when Republicans are feeling battered and need a path back to electoral viability, Schumer has embraced Obama’s old bipartisan religion in a move to realize the president’s second-term agenda, and in the process attain so-far-elusive legislative accomplishments to solidify his power and status in the Senate.

In the past, the media-hungry Schumer might have simply elbowed his way onto center stage, a move common enough that his colleagues came to dub it “getting Schumered.” This time, the president is focusing on bringing along the public and giving Schumer room to work the Senate. Other Democrats are signing on, and key Republicans are eager to work with him.

Schumer is not one to let the opportunity slip away. On Monday, he led a bipartisan group of top lawmakers during a jampacked news conference, unveiling a framework for immigration reform. That night, he was instrumental in securing bipartisan support for a $60 billion relief package for victims of Hurricane Sandy. On Tuesday, he appeared with Sen. John McCain (R-Ariz.) on MSNBC’s “Morning Joe” to tout bipartisan support for the immigration package. On Wednesday, the duo had a return engagement at a Politico Playbook breakfast, where McCain said Schumer was assuming the role of the late senator Edward M. Kennedy of Massachusetts as the Democratic lion able to bridge the partisan divide. Later that day, Schumer said at a gun-control hearing that “as we meet here today, I’m having productive conversations with colleagues on both sides of the aisle” to introduce new legislation.

In his long ascent to power, Schumer has distinguished himself as one of the most aggressive, politically calculating and effectively partisan Democrats in the country. As chairman of the Democratic Senatorial Campaign Committee (DSCC) from 2005 to 2009, he fought to build, guard and expand the Democratic majority that he aspires to, and in many ways already does, lead. The 2010 reelection of Sen. Harry M. Reid (D-Nev.), whom Schumer calls his “foxhole buddy,” temporarily took the brass ring of majority leader off the table. But as this month has demonstrated, it hasn’t sapped his ambition.

(Schumer, loath to upset his budding relationships with Republicans, declined an interview request.)

Grumbling in the caucus

At the Monday morning news conference on immigration, Schumer, who spent much of last year excoriating Republicans for alienating Hispanics, said, “we do not want immigration as a wedge issue” and lauded McCain as “the glue in our group.” He nodded emphatically as Sen. Marco Rubio (R-Fla.) spoke. According to people familiar with the talks that produced the outlines of an immigration proposal, the New Yorker made concessions to help get Rubio on board and persistently appealed to the young Cuban American senator and presumptive 2016 presidential candidate.

Asked at the news conference why the senators were getting out in front of the White House’s immigration announcement on Tuesday, Schumer said, “It seems to me, at least, that the Senate is the most fortuitous place to move forward first.”

And what of Obama’s own vision for immigration reform, and his assertion in Nevada that “my hope is that this provides some key markers to members of Congress as they craft a bill”?

“The president is handling this perfectly,” Schumer said in a statement, adding, “He is also giving lawmakers on both sides the space to form a bipartisan coalition.”

Translation: Steer clear.

Despite his newfound bipartisan fervor, Schumer — the policy and messaging point person for Senate Democrats — has earned a reputation among his critics in the caucus as something of a freelancer. When House Republicans backed down from threats to link spending cuts to the raising of the debt ceiling, Schumer gleefully said the GOP was in “full retreat” on fiscal issues. He then climbed over his colleagues to beat back Republican threats to abandon their position if Democrats didn’t pass a budget in the Senate.

The Republicans unveiled their talking points on a Friday. On Saturday, Schumer called new Senate Budget Committee Chairman Patty Murray (D-Wash.). Schumer, who was scheduled to appear on the Sunday political talk shows, wanted to reveal their intention to pass a budget with increased revenue — but in the larger, and Republican-friendly, framework of tax reform. Murray told Schumer the news was not his to break, according to several sources with knowledge of the call. But waiting was anathema to Schumer’s respond-to-everything-in-24-hours philosophy.

“We Democrats have always intended to do a budget this year,” he said on NBC’s “Meet the Press” as he articulated the Democrats’ plans.

Schumer subsequently suggested that the budget could be drafted through a fast-track process that avoids gridlock but limits the potential scope of tax-code reform. That approach essentially undercut the proposal that Finance Committee Chairman Max Baucus (D-Mont.) had been working on for years. And when Baucus — still furious — next saw Schumer on the Senate floor, he approached to express his displeasure, according to several congressional sources.

A person familiar with Schumer’s thinking said that “sometimes as a member of leadership, you need to bring decision-making to a head, and it causes ruffled feathers.”

Schumer’s gamesmanship doesn’t always engender warm feelings, but it often gets results.

This month, a group of senators led by Jeff Merkley (D-Ore.) and Tom Udall (D-N.M.), both elected in 2008 while Schumer was head of the DSCC, spearheaded an effort to alleviate paralysis in the Senate by reforming the rules governing filibusters, the tactic that allows the minority to block consideration of legislation. According to a source with knowledge of the negotiations, Schumer, the chairman of the Rules Committee, told Merkley he’d support his reform if the Oregonian could find 51 votes, something Schumer and Reid doubted was possible. Merkley used Schumer’s support as a selling point but ultimately couldn’t find the votes.

Republicans, however, didn’t know that, and feared that Democrats would try to strip the minority of its power to filibuster. Schumer then agreed to join McCain in a bipartisan group opposing the bold overhaul in favor of a more modest reform. “Ultimately,” Merkley said, “what we did was go with something that was essentially a strategy of saying, ‘We should still try to do this in a bipartisan fashion.’ ”

McCain was grateful. “A lot of people don’t appreciate how important it was for us to get that done,” he said at the immigration news conference. “Chuck Schumer and I and others — and Dick Durbin — were involved in a bipartisan effort to avert that.”

Schumer’s greatest legislative achievement to date came as a congressman, when he wrote the assault weapons ban that passed as part of then-Sen. Joseph R. Biden’s 1994 crime bill. As he rose to the Senate, Schumer became a significantly less vocal champion of gun control, which came to be seen as political poison to Democrats. Aides to Mayor Michael R. Bloomberg (I) of New York, who has been a singular and consistent advocate of gun control, privately refer to Schumer’s backtracking as a clear example of Democratic cowardice.

Now that national tragedies and political willpower have made gun control politically palatable again, Schumer is back in the fray. And while he is involved in efforts to again ban assault weapons — considered a long shot by many — most of his energy is going into lining up support from National Rifle Association-approved senators, including Democrat Joe Manchin of West Virginia and Republicans Mark Kirk of Illinois and Tom Coburn of Oklahoma, to strengthen background checks, a more modest and promising approach.

A solid political base

Schumer’s freedom to act across such a broad swath of policy in Washington is rooted in his strength in New York, where he pays obsessive attention to the most narrow of local issues. His Sunday morning news conferences, covering such topics as cereal price gouging, have become an institution.

Al Sharpton, the New York reverend turned talk show host, said Schumer “hasn’t allowed his expanded stature to disconnect him from the ground.” Sharpton said he received a call from Schumer on the day of his event marking Martin Luther King Jr. Day, asking him to explain to attendees that he couldn’t be there because he was preparing for the inauguration. “That’s something that has made him more powerful at home because his base is covered,” Sharpton said.

Schumer, who began that week with the presidential inauguration, ended it with a whirlwind of local events from Manhattan to Long Island to the Bronx. It all culminated at the place his career began, Brooklyn.

“Schumer! Schumer! We got Schumer!” Lupe Todd called out from the corner of an auditorium at Pratt Institute. Her boss, Hakeem Jeffries, a rising Democratic star and new Brooklyn congressman, was being sworn in, and Schumer was the first and most important elected official slated to speak. But the senator was more than a half-hour late.

As the crowd had bided its time, Schumer had been in his car, on a conference call about the rollout of gun and immigration proposals. Upon spotting Schumer, Todd dispatched an aide to lead him to the section reserved for elected officials. Schumer stomped and waved his way happily down the aisle, bypassing his seat and heading directly to the Jeffries family, enclosing the event’s star in a bear hug. Once seated, Schumer happily kept rhythm with the church choir onstage, smacking a program on his knee. The city’s mayoral candidates, councilmen, the ghost-writer of Schumer’s book, a black pastor, an Orthodox Jewish rabbi and a Muslim imam all stared at the back of his bobbing head.

So did Vito Lopez, the embattled former boss of the Brooklyn Democratic machine, who knows a thing or two about raw power. “New York state has not had someone of the stature and position of a U.S. senator of the caliber of Chuck Schumer in maybe 40 or 50 years,” Lopez said. “More importantly, he is a professional politician.”

The emcee introduced Schumer as the New Yorker who had spent Inauguration Day with Obama, and the senator climbed the stage to the cheers of the predominantly black crowd.

Schumer knew his audience. He made reference to his Brooklyn high school (“Our team’s motto at Madison was, ‘We may be small, but we’re slow’ ”) and told Jeffries from the stage that “you and I are going to be partners in banning assault weapons and getting these guns off our streets.”

He concluded by evoking “the first inauguration I was at this week” and talked about his close consultations with Obama. “I told him in the limo,” Schumer said, “ ‘Don’t worry, we have your back, Mr. President. Go forward and move forward.’ ”