All eyes will be on Gov. Bobby Jindal when he kicks off the 2015 legislative session Monday afternoon with a speech to all 144 legislators in the high-ceilinged Louisiana House chamber.

But the person who will matter most to those in the room — and in many ways will be more powerful than the governor himself — will be the man with the full head of gray hair sitting in the black swivel chair directly behind Jindal: Senate President John Alario.

With the governor increasingly absent and unpopular, legislators and political analysts say, the major role in solving the biggest task before the Legislature — how to plug the monumental $1.6 billion budget deficit — will fall to Alario.

“Alario is obviously the key deal-maker,” said Robert Scott, president of the Public Affairs Research Council of Louisiana, a governmental policy think tank. “He’ll be the one who has the most control over what does and doesn’t get done. He’s someone everyone knows they need to go to.”

One small example of this: After state Rep. Harold Ritchie, D-Bogalusa, held a news conference on Tuesday to announce a measure that would raise cigarette taxes by $1.18 per pack, Ritchie said his next move would be to try to get Alario’s blessing.

During 43 years in the Legislature — longer than any other current member — Alario, R-Westwego, has achieved an unmatched record as the only legislator to serve as House speaker twice and Senate president once. He has won those positions by gaining the trust of other lawmakers as a leader who will keep his word and do all he can to limit votes that will cause trouble back home.

Alario, a 71-year-old widower and grandfather of five, operates like an old-style pol, reminding veteran observers of former U.S. House Speaker Tip O’Neill. An accountant by trade, Alario works behind the scenes, quietly moving the pieces on the political chessboard, never trying to win over members with an impassioned speech.

He is forever handing out favors to legislators: a choice Capitol parking space here, favorable consideration of a bill there, making sure the budget contains funding for a certain park back in someone’s district, flattering a lawmaker by telling a group visiting the State Capitol that he or she is doing a bang-up job.

In return, lawmakers are willing — eager, even — to back Alario on big votes.

In 2014, the Senate passed the state budget on a 37-1 vote. The House vote was 76-24.

“There’s not an offensive scheme or a defensive scheme he hasn’t seen along the way,” said Bubba Henry, a business lobbyist who served as House speaker for two terms in the 1970s. “He wins votes by winning friends.”

Despite his deep, deep ties to the Legislature, Alario throughout his career has shown a desire to serve the political agenda of whoever holds the office of governor.

He already has quelled a potential rebellion this year by legislators who are angry with Jindal’s insistence that he will adhere to the anti-tax pledge championed by Grover Norquist’s Washington-based group, Americans for Tax Reform.

In a March 12 meeting in his office with House and Senate leaders, Republicans and Democrats alike, Alario allowed everyone to offer their views first and then told them that they must not challenge the anti-tax pledge.

“It will be much easier to get things done if we stay within the swim lanes,” Alario said in a telephone interview.

Jim Richardson — an LSU economist who for more than 25 years has sat on the four-member panel that determines the amount of revenue the state can spend — said Alario is well aware that he needs 26 votes in the 39-member Senate to override a gubernatorial veto, meaning Jindal can use all the powers of his office to hold as few as 14 votes. With a limited legislative agenda, Jindal will mostly be playing defense with the threat of a gubernatorial veto.

“John is a practical man,” Richardson said.

That was evident in 2010 when Alario quietly switched to the Republican Party after a lifetime as a Democrat, having served as speaker twice under Gov. Edwin Edwards, a populist Democrat, and having traditionally enjoyed the support of organized labor and the legislative black caucus.

“Whether I’m a Democrat or Republican or the Whig party, I’d like to be president of the Senate,” Alario said then, according to The Times-Picayune.

A year later, after Alario had quietly lined up the votes, Jindal said he wanted the former Democrat to be his next Senate president.

Alario’s closeness to governors and his positions of leadership in the Legislature have paid off at home. State dollars funded the creation in Westwego of the John A. Alario Sr. Event Center — named after his father, a fisherman and maintenance engineer — which hosts sports events, high school graduations and corporate gatherings.

Alario also has steered millions of taxpayer dollars to reconstruct the Huey P. Long Bridge, to build the TPC golf course, which hosts the PGA Zurich Classic of New Orleans, and to upgrade Bayou Segnette State Park.

Alario’s approach to lawmaking has not always served taxpayers well, in some observers’ opinion. The budget approved by Jindal and lawmakers last year contained a record $1.05 billion in one-time money — funds that aren’t available to legislators this year. Richardson and others blame the Legislature’s increasing reliance on one-time money for the deep budget hole the state now faces.

“Nobody put a gun to the head of legislators over the past seven years and made them embrace everything Bobby has proposed,” state Treasurer John Kennedy said.

Under the state Constitution, bills that would raise taxes must originate in the House. Speaker Chuck Kleckley, R-Lake Charles, said the House and Senate must work closely together this year. “It’s a very critical time for our state,” he said.

To be sure, Alario has an advantage in forging unity in the relatively small Senate, but he uses every lever at his disposal to build relationships with his colleagues.

For example, he regularly invites senators to join him for supper at the Senate president’s state-owned apartment at the Pentagon Barracks, across from the Capitol. He said he likes to cook crab soup, spaghetti and chicken with butter beans.

“I find it’s a lot easier, after debating all day, to get together in an informal setting where you can have an adult beverage now and then and see that you have the same concerns as each other,” Alario said. “When you understand each other, it makes it easier to work together.”

In sharp contrast, Jindal has increasingly become a spectral presence for legislators, especially during the past year, when he has stepped up preparations for a possible presidential campaign by traveling repeatedly to Iowa, New Hampshire and other early presidential election states. Jindal was out of the state 165 days in 2014, The Advocate reported.

Alario last visited with Jindal on March 30, during what he described as a “social gathering” at the Governor’s Mansion. Kleckley said he could not remember the last time he met with the governor.

It likely was on Feb. 25, when he, Alario and Sen. Jack Donahue, R-Mandeville, who chairs the Senate Finance Committee, got a briefing from Jindal on the governor’s budget that he would release in two days. Rep. Jim Fannin, R-Jonesboro, who chairs the House Appropriations Committee, participated by telephone.

Sen. Neil Riser, R-Columbia, will play a key role this year because all tax legislation will pass through the Senate Revenue and Fiscal Affairs Committee, which he chairs. Riser said he has seen the governor only once in recent months, at a Christmas party.

Asked why they hadn’t met in recent weeks, Riser said, “I don’t know. You’d have to ask the governor. I’m not that hard to get a hold of.”

Jindal traveled to Iowa on Thursday to speak to parents who home-school their children, a key conservative constituency, and then went to Tennessee to speak to the National Rifle Association’s Leadership Forum on Friday. He was not available for an interview, his staff said.

While Alario commands nearly universal respect in the Capitol, questions have been raised whether he has misused his power.

In 1992, he won passage of the hotly contested land casino for New Orleans by secretly telling the House clerk beforehand to shut down the electronic voting procedure several seconds early, before some members had cast their final votes. The bill passed with no votes to spare. Opponents howled in protest.

A year ago, nola.com and WVUE Fox 8 reported that Alario spent $705,000 between 2009 and 2012 in campaign money to rent a suite at Tiger Stadium for LSU football games, to lease and repair cars, to buy tickets for Saints and Hornets games and to pay for meals at expensive restaurants.

The report doesn’t seem to have hurt Alario within the Capitol.

“I don’t know who the next governor will be,” said Sen. Ronnie Johns, R-Lake Charles. “But I would bet that the next Senate president will be John Alario.”

Mark Ballard, of The Advocate Capitol news bureau, contributed to this report. Follow Tyler Bridges on Twitter, @TegBridges. For more coverage of the State Capitol, follow Louisiana Politics at http://blogs.theadvocate.com/politicsblog.