Former Florida governor and expected Republican presidential candidate Jeb Bush attended an economic conference in Berlin on Tuesday. (Axel Schmidt/Getty Images)

A super PAC backing former Florida governor Jeb Bush is likely to fall short of collecting $100 million by the end of this month, despite widespread expectations that the group would hit that record-breaking sum, according to people close to the operation.

The exact size of the war chest is closely held, but two individuals familiar with internal discussions believe the total that the Right to Rise super PAC will report in mid-July could be substantially lower than the nine figures that senior Republicans have anticipated.

That would be a major psychological blow for Bush’s operation, whose fundraising prowess has raised expectations about how much cash it has been amassing. Bush’s schedule for the past five months has been dominated by high-priced fundraisers for the super PAC, helping the group stockpile tens of millions.

Bush, once considered the GOP’s most formidable presidential contender, has revamped his campaign organization amid middling poll numbers and strong competition from other candidates. He is spending this week in Europe, bolstering his foreign policy bonafides, before officially announcing his campaign in Miami on Monday.

While his aides never publicly declared that the super PAC would hit $100 million, they did little to tamp down such predictions — and in some cases privately fueled them, according to top GOP fundraisers.

Mike Murphy, the strategist overseeing the super PAC, declined to comment, except to say: “At the right time, we will release very formidable numbers.”

It is possible that Bush will approach the $100 million figure if his campaign includes the entire sprawling political apparatus that he and his allies have built since January. By the end of the month, that operation will include a super PAC, a leadership PAC, a nonprofit and the soon-to-be announced campaign.

The super PAC may also have substantial pledges from wealthy donors who plan to expand on their initial contributions after this quarter, which ends June 30. In its early months of fundraising, the group was so awash in cash that it temporarily capped donations at $1 million.

The fundraising haul that the super PAC will report on July 15 is still bound to be historic. Bush told donors in April that the operation had raised more money in its first 100 days than any other Republican organization in modern history.

But any figure short of $100 million will probably be seen as a sign of weakness by senior party strategists and donors, many of whom now expect the group to greatly exceed that total.

“I will be shocked if it is not $100 million or more,” said one veteran bundler raising money for Bush, who spoke on the condition of anonymity to discuss private conversations about the fundraising.

The built-up expectations underscore the dramatically inflated atmosphere of this year’s money race.

When Bush’s brother George W. Bush launched his first presidential bid in 1999, he stunned the field by raising a record $37 million in four months. But that was before the advent of super PACs, which can accept unlimited sums from individuals and corporations.

The early, prominent role being played by those independent groups this year gives candidates with just a few wealthy backers the ability to compete. A network of super PACs supporting Sen. Ted Cruz (Tex.) claims to have raised $37 million so far, while super PACs backing Sen. Marco Rubio (Fla.) and Wisconsin Gov. Scott Walker are believed to be bringing in millions.

But it has been Bush, more than any other White House contender, who has put a heavy emphasis on raising big money before announcing his candidacy. His team laid out presidential-style goals for fundraisers, asking them to hit targets of $50,000, $100,000, $250,000 or $500,000 by April 17. Tickets to some high-priced events were $100,000 a person.

That fueled perceptions that the super PAC will post an eye-popping figure in its first report. Bush aides have done little to push back against such speculation, and there has been no evidence of a last-minute scramble to pack in late fundraisers for the group.

Instead, in recent days Bush’s team has turned its focus to raising money for his presidential campaign committee, which can accept donations only up to $2,700. The new goal for fundraisers: to bring in $27,000 during the last 15 days of the month.