Republican presidential candidate Jeb Bush at a candidate forum in Manchester, N.H., on Dec. 8. (Brian Snyder/Reuters)

The super PAC supporting Jeb Bush is racing through its massive war chest much faster than money is coming in, spending close to $50 ­million in a record blitz that has so far failed to lift the former Florida governor’s sputtering presidential candidacy.

The group, Right to Rise, has already gone through nearly half of the $103 million it brought in during the first half of the year, records show. It raised only about $13 million in the five months that followed, according to a person familiar with the figure.

That leaves the super PAC with about $67 million heading into the first 2016 GOP nominating contests. The sum still surpasses the resources of rival groups, but it is not clear whether Right to Rise’s financial might — viewed earlier this year as Bush’s distinct advantage — will be enough to help separate him from the pack.

The group’s muted impact so far represents a confounding reality of this year’s unconventional campaign: Money is no longer a clear barometer of success.

The wall-to-wall media coverage of Republican front-runner Donald Trump has deflated the value of a bulging war chest that can finance costly television commercials. And the deluge of gauzy spots touting Bush’s conservative record has not eliminated deep skepticism in the GOP base about his establishment ties and family name, party operatives said.

The super PAC supporting Republican presidential candidate Jeb Bush released an ad Dec. 7 questioning the merits of candidates Donald Trump, Marco Rubio and Ted Cruz. The ad is set to air in Iowa, New Hampshire, South Carolina and Nevada. (Right to Rise USA)

“You’d always rather be the one with the money,” said veteran Republican strategist Scott Reed. “But clearly, this cycle we’re learning that money doesn’t buy you love.”

In all, Right to Rise has reported spending more than $49 million to bolster Bush’s White House run, according to campaign finance filings — a massive investment that far outstrips the efforts of other independent groups at this point in past presidential races.

The total — which does not include any money the group has spent on staff, polling and other operating expenses since the end of June — is close to five times what any other candidate-aligned super PAC has reported spending this year, according to Federal Election Commission reports tallied by the Sunlight Foundation’s Influence Explorer.

Despite the gusher of door hangers, mailers, online ads and TV spots produced by Right to Rise, however, Bush hovers between 3 and 5 percent in national polls — down from 12 to 15 percent in mid-July.

In Iowa, where Right to Rise has spent nearly $9.4 million since late June, Bush remains stalled in single digits. After the group blanketed New Hampshire with $18.5 million worth of TV ads and yard signs touting Bush, he dropped from a double-digit standing to between 5 and 9 percent support. And in South Carolina, he has fallen out of the top three among GOP presidential contenders, despite a $6.5 million super-PAC barrage on his behalf.

It is a situation that few predicted earlier this year, when Bush spent nearly six months helping stockpile the super PAC with huge checks before officially declaring his presidential bid. With his longtime political adviser Mike Murphy at the helm, the group was widely expected to be a dominant factor in shaping the 2016 nomination fight.

“Our job is just to amplify his story and what he’s saying, and we banked enough cash that nobody’s turning our speaker off,” Murphy told Bloomberg Politics in October.

In recent private meetings, Murphy has continued to express confidence in the super PAC’s value and Bush’s prospects, arguing that a large share of voters have not settled on a candidate. During an early-morning breakfast meeting for Right to Rise supporters in Washington last week, he predicted that the group’s investments in ads touting Bush’s biography and gubernatorial record will pay dividends once the electorate focuses on its choices.

That argument has assuaged many of the super PAC’s biggest backers.

“Like everyone else, I’m looking at the numbers,” said Mel Sembler, a Florida developer and former ambassador in both Bush administrations who is helping raise money for Right to Rise. “The political people keep assuring us that the polling numbers are not important at this time. Mike Murphy gave us confidence that things would start turning around when people begin voting.”

Al Hoffman, another Florida developer and former ambassador who has given the super PAC $1 million, said he was impressed with a new 15-minute biographical documentary the group rolled out this weekend.

“Once the serious-minded Republicans who are going to vote in the primary see it, that will have big impact,” he said.

Still, there are signs that Right to Rise is recalibrating to contend with Trump’s durability. Back in August, Murphy declared the real estate mogul “other people’s problem.”

“If other campaigns wish that we’re going to uncork money on Donald Trump, they’ll be disappointed,” he told The Washington Post at the time.

But this week, in its first TV ad hitting other GOP candidates, Right to Rise went after the national security credentials of Sen. Ted Cruz of Texas, Sen. Marco Rubio of Florida — and Trump.

“When the attacks come here, the person behind this desk will have to protect your family,” a male narrator says as the grinning reality-television star is pictured seated in the Oval Office. “Will he be impulsive and reckless like Donald Trump?”

Murphy did not respond to a request for comment on the super PAC’s strategy. Paul Lindsay, a spokesman for the group, declined to say whether Right to Rise plans to put a particular focus on Trump in the coming weeks.

“Our investments are long-term and focused on helping Jeb achieve a general election victory in November 2016,” Lindsay said in a statement. “We’ve built a strong foundation in introducing Jeb to voters, and we’re moving to a new phase where we’ll talk about his plans for the future and the records of the other candidates in the race.”

Bush supporters argue that the super PAC’s work is paying off by keeping him front and center as voters begin to narrow their choices, but even allies acknowledge that a torrent of TV commercials does not have the same influence this year as it did in past elections.

“Because of the many channels of information across all these media platforms, paid advertising is having as limited an effect as anyone can recall,” said Rob Stutzman, a Sacramento-based GOP strategist who is backing Bush.

“And it’s fairly obvious that who Jeb is is not thus far what most Republican primary voters have been looking for,” he added. “Now, when they start going to the polls, we will see if that changes.”

The super PAC is still collecting sizable checks, backers say, and hopes to bring in as much as $20 million total in the second half of the year.

Jeanne Phillips, a major GOP fundraiser in Dallas who organized George W. Bush’s inaugurations and is now helping collect donations for Right to Rise, said the super PAC’s donors have remained steadfast.

“The polls are great for media and pundits and all of that, but at this point I don’t take them very seriously,” she said, adding, “You want your candidate to have a slow peak.”

Phillips is on the super PAC’s three-member donor governance committee, along with Sembler and Ray Hunt, the executive chairman of Hunt Consolidated, the privately held energy and ­investment holding company where Phillips also serves as a senior executive.

The committee does not set political strategy, but the trio oversees how the super PAC is spending its money. The arrangement underscores how wealthy contributors are asserting a stronger role in the management of independent groups this cycle.

Among the measures the committee put in place: a cap on overall compensation for Murphy and many of the super PAC’s top vendors.

Murphy is being paid through his Virginia-based firm, the Revolution Agency, which has received $3.3 million from Right to Rise for ad production and airtime. Charlie Spies, the super PAC’s treasurer, declined to disclose how much Murphy is earning but said that “it is far lower than anything I have seen for a general consultant in his position.”

Out of the nearly $44 million that Right to Rise has spent on ad buys, mailers and yard signs, $39 million has been directed to a limited liability company called Oath Strategies. The firm was formed in June by veteran GOP ad buyers Brad Mont and Patti Heck to serve as the super PAC’s main media buyer.

“That was the easiest way for us to figure out how to handle a big client like this,” said Mont, who has worked with Murphy for the past three decades, including a stint at his ad firm.

Much of the money paid to Oath Strategies has been passed along to local TV stations to purchase airtime. Mont declined to disclose the size of the commission that he and Heck receive, but he and super-PAC officials said it is a much smaller percentage than is typical.

“What we’re paying for media buying is the lowest that I’ve ever seen,” Spies said.

The large volume of purchases is likely to continue. On Tuesday evening, a team of Right to Rise videographers were on hand at a Bush event at an American Legion hall in Hooksett, N.H., filming the scene with expensive high-definition cameras to capture potential footage for future spots.

It remains to be seen whether the coming ads will break through to voters. In the crowd, Phyllis Butler, a retired corrections officer, strained to recall which TV ads have been the most memorable.

“We see a few on Cruz and Bush,” she said. “I guess Trump — I don’t know if they’re ads per se, but his face is always on the news. He’s monopolizing the news.”

Ed O’Keefe in Hooksett and Scott Clement and Alice Crites in Washington contributed to this report.

Correction: The name of Hooksett, N.H., was misspelled in an earlier version of this article.