It’s official: Jeb Bush is no longer the leading contender to become the Republican candidate for president. Instead, prediction markets now rate Marco Rubio as far more likely to get the nod.

One broad measure of the betting markets puts Mr. Rubio’s chances at 34 percent versus Mr. Bush’s at 23 percent.

The extent of this reversal is stark. Mr. Bush’s name recognition, executive experience and links to the Republican establishment led the betting markets to rate him the most likely winner even before he announced his candidacy. He took an early and commanding lead in fund-raising and won the most endorsements from fellow Republicans. He also led in most national polls, at least until mid-July, when Donald Trump wrestled the national spotlight from him and has continued to entertain its bright glare. Recent polls suggest that only around 7 percent of potential Republican voters plan to vote for Mr. Bush.

“We’ve made an adjustment in our campaign,” Bush said Saturday before conducting a town hall in the pivotal state of South Carolina. “That’s what leaders do.”

Stumping the Palmetto State a day after his campaign announced staff reductions and pay cuts, Bush dismissed critics who said the changes reflect a struggling campaign that is losing ground to any number of rivals.

“Blah, blah, blah,” Bush said. “That’s my answer — blah, blah, blah.”

Jeb Bush will attend a finance meeting this weekend in Houston convened by former President George H. W. Bush and attended by Bush’s brother, former President George W. Bush, CBS News has learned.

The session, designed to assess where Bush’s candidacy stands in the face of large-scale staff cutbacks and underwhelming poll numbers, will also be attended by Bush’s mother, Barbara Bush. The governor’s campaign confirmed the meeting will be held Sunday and Monday…

A GOP source who interacts regularly with the Bush campaign said there is a “donor revolt in progress,” as early Bush backers have grown dismayed over the reversal of their candidate’s fortunes.

Complaints are more frequent about the Bush inner circle and Bush’s message, schedule and intensity.

More immediately, the Republicans’ third debate, on Wednesday night, now looms as a potentially decisive moment for several candidates — above all Mr. Bush, whose performances have been lackluster so far, and whose staid, sober manner is proving an ill fit with voter discontent with long-serving elected officials…

In Miami, where Mr. Bush’s campaign is based, aides were on edge Friday. Many were waiting to hear whether they would receive pay cuts, be sent to an early state or laid off entirely. The mood was brighter among those already in early states, who have been seeking more of Mr. Bush’s time and now will apparently get it. According to an internal memo, first reported Friday by Bloomberg News, Mr. Bush plans to reduce payroll costs by 40 percent this week and cut travel spending by 20 percent…

Some Bush strategists grumbled about what they described as an excessively large infrastructure at the headquarters. One department that will be particularly thinned out, advisers said, is the group of video producers and editors, called “Jeb TV,” that was assembled for what had been a robust digital effort.

One major Bush fundraiser, requesting anonymity to speak candidly, said of the Bush team: “They’ve finally woken up and realized that Trump may be for real. Initially, they thought, ‘This clown will self-destruct.’ It hasn’t happened.”…

“They don’t have a staff problem,” said one presidential campaign veteran who requested anonymity to offer a candid assessment. “They have a candidate performance issue. The candidate better get better — very fast.”…

But one Bush fundraiser who requested anonymity to speak freely said: “It feels very much like a death spiral, and it breaks my heart. I don’t know anyone who wants to reinvest now.” The campaign, this person added, has been “head-scratchingly bad in every element. I wouldn’t be shocked in 60 days from now if he wasn’t in the race.”

“Jeb’s just blended into the second tier of the Republican pack,” said Doug Corn, an Ohio-based financial adviser and top fundraiser for George W. Bush who hasn’t donated to a candidate this year. “When you run for president, you have to be very charismatic, you have to articulate extremely well and you have to show unbelievable amounts of passion.”…

Nearly half of the leading donors to his brother’s 2004 re-election who are still alive appear to be on the sidelines, while about 15% have peeled off to a dozen other candidates, including Mr. Christie and Mr. Rubio, according to a Journal review of Federal Election Commission filings. (Super PACS haven’t reported donations since June 30.)

Only about one out of four of George W. Bush’s “Rangers” —those who raised at least $200,000 in 2004—have each bundled at least $17,600 for his brother’s campaign, according to a list released last week. Another 15% have given to a super PAC backing Mr. Bush or made a smaller donation…

“When I see him on television, he seems like he’s stumbling,” said Travis Thompson, a former Ranger and GOP national committeeman from Hawaii who hasn’t committed to a candidate. “The fact that he did an excellent job in Florida isn’t turning people on.”

“The moment is now,” said New Hampshire state Rep. Carlos Gonzalez, reflecting the sense of urgency among nearly two dozen Bush supporters interviewed this past week by The Associated Press…

But interviews with supporters in early states reveal concerns that extend far beyond the campaign’s allocation of resources. There are fears Bush is failing to distinguish himself from his rivals, despite a month of aggressive television advertising. Many said they were eager to see Bush be more assertive and forceful in debates, in his TV ads and at campaign appearances…

“God gives us our personalities and our looks and we can’t help that,” said Robert Rowe, a New Hampshire state representative who is switching his allegiance from Bush to Ohio Gov. John Kasich. “We are who we are.”

Said Bush supporter Steven Zumbach, an attorney from Des Moines, Iowa: “He’s going to need to take some risk. Unless he does something like that, it’s going to be difficult.”

When Bush’s su­per PAC began its early-state ad­vert­ising blitz in Septem­ber, a seni­or Bush cam­paign op­er­at­ive said it would be fair to draw con­clu­sions of its ef­fect­ive­ness in a month’s time. We’re at that point now, and the cam­paign’s de­cision to shake things up tells you everything you need to know about the res­ults. 

Bush has been out­spend­ing his rivals on tele­vi­sion, and usu­ally that trans­lates in­to mo­mentum in the polls. But in Iowa, Bush is lan­guish­ing in fifth place at 5 per­cent—tied with Rand Paul—in the new Bloomberg Polit­ics/Des Moines Re­gister poll of likely Iowa caucus-go­ers. A near-ma­jor­ity of Iowa Re­pub­lic­an voters (47 per­cent) said Bush’s “fam­ily ties” were a neg­at­ive in their per­cep­tion of the can­did­ate. In the cru­cial state of New Hamp­shire, Bush polls just 10 per­cent in this week’s Bloomberg/St. An­selm’s Col­lege poll—in third place. Across the board, his fa­vor­ables haven’t budged much from when he first entered the race. His case as the most elect­able Re­pub­lic­an has evap­or­ated; his fa­vor­ab­il­ity with the gen­er­al elect­or­ate is still badly un­der­wa­ter (33/49, in The Huff­ing­ton Post’s polling av­er­age).

All this sug­gests Bush faces fun­da­ment­al chal­lenges that will be hard to al­ter with money, ad­vert­ising, and even a staff shake-up. His polit­ic­al pro­file is badly dis­con­nec­ted from the angry, dis­af­fected, anti-Wash­ing­ton mood of the Re­pub­lic­an elect­or­ate right now. He could be the right can­did­ate at the wrong time for Re­pub­lic­ans. 

Jeb Bush cannot win. I don’t say this because I dislike Jeb. (On the contrary, I think he has virtues as both a candidate and a person.) But the numbers don’t lie. It’s not just that his ratio of big-donor to small-dollar donations is vastly out of sync with the rest of the GOP and Democratic fields today. (Even Romney’s ratio of small-donor to big-donor dollars was more than twice Jeb’s.) Jeb’s big-donor to small-donor ratio is 15:1. No candidate has ever won the nomination with such a heavy reliance on big donors, even at a time when big-donor money made up a much larger percentage of total fundraising. For the rest of the GOP field, the ratio of big-donor to small-donor money is 1:1.6. Furthermore, Jeb ranks just third in total fundraising. For reasons I examine below, that seems unlikely to improve…

But what about the super PAC? Jeb supporters might counter. Yes, that money would certainly be helpful for Jeb, but it has severe legal limits as to its usage — and he’s already spent millions of it on TV in early-primary states, with little to show for it. The super-PAC money just further emphasizes his reliance on wealthy donors.

And it won’t get him over the top. Meg Whitman spent more than $178 million (far more than is in Jeb’s super PAC) to take just 40.9 percent of the vote in the governor’s race in one state, California, during the 2010 election. She ran just a point ahead of California GOP lieutenant-gubernatorial candidate Abel Maldonado, who spent less than $2 million on his entire campaign. As conservatives always say to campaign finance “reformers”: You cannot buy elections. The GOP establishment needs to take this to heart and realize that in Jeb, it has a lost cause.

I sensed trouble when practically no one I knew in Florida Republican activist circles was supporting Jeb’s campaign and these were the same people who knew him best. Moreover, they all personally liked him, and twice helped elect him governor…

[A]s Barbara Bush astutely said in 2013, “He (Jeb) will get all our enemies and half of our friends.” However, she got the second part wrong because recent polls indicate that Jeb is down to less than a quarter of “our friends.”

Unfortunately, because Jeb did not heed his Mother’s warning, a great American political family, that has served our nation honorably, is likely to suffer a major political defeat in the Florida primary on March 15, 2016 and then Jeb’s campaign will be history.

The people cashing Jeb’s checks will, of course, argue that this is all incredibly premature. Bush can keep running for months and always drop out and endorse Rubio later if that’s needed as some kind of stop-Trump or stop-Cruz gesture. And just because Rubio is better at politics than Bush (can you imagine someone with Bush’s talents making it as far as Rubio has if he’d had Rubio’s same modest origins) doesn’t mean that Bush can’t ultimately bury him under an avalanche of money. After all, several not-very-talented members of Bush’s immediate family have gotten to the White House ahead of other, more compelling options.

That said, for months now the Bush campaign has gone nowhere but down. The more people see of Bush, the more they feel “meh” about him. If he quits now for the good of the party, people will say he was a good man driven by a strong sense of duty and noblesse oblige. If he waits for months as his public support continues to bleed away, he’ll be humiliated.

Noting that Donald Trump had vowed to drop out of the presidential race if his poll numbers collapse, Fox News’ Megyn Kelly asked Bush, “What would it take to make you get out?”

“I’m not getting out. I believe we have a plan to be very competitive in the early states. We have the resources to stay with this,” Bush told Kelly. “I’m campaigning hard, I’m campaigning with heart, I’m campaigning in a way that will draw people towards our cause.”

“This is the beginning of a hard race. I never thought it would be easy and it certainly hasn’t been. … I believe that I’m gonna win the nomination,” he said.