When the pressure was on this past week, Clinton rose to the occasion and gave her campaign a huge boost. Now it’s Bush’s turn. Photograph by Johnny Louis / FilmMagic / Getty

The contrast couldn’t have been more stark. On Friday, as Hillary Clinton was basking in the reaction to her marathon appearance before the House Select Committee on Benghazi, her communications director, Jennifer Palmieri, told reporters that the hour between nine and ten o’clock on Thursday night, after the hearing finally finished, was the campaign’s best fund-raising hour yet. And also on Friday, A.F.S.C.M.E., the largest public-sector union in the country, announced that it was endorsing Clinton for the Presidency—an important win in her tussle with Senator Bernie Sanders for the backing of organized labor.

Meanwhile, the campaign of the supposed Republican front-runner, Jeb Bush, was letting it be known that it was laying off people and slashing its payroll by forty per cent. It’s well known that the Bush campaign has been spending heavily, and there have been persistent rumors that, with the candidate trailing badly in the polls, its fund-raising efforts had stalled. Evidently, these rumors were accurate. Seeking to put a positive spin on things, the Bush campaign portrayed the cost-cutting as an effort to play the long game and direct resources toward the early primary states—Iowa, New Hampshire, South Carolina. “This is about winning the race,” a Bush adviser told Bloomberg Politics. “We’re doing it now and making the shifts with confidence. We expect to win.”

Campaign advisers have to make such statements. But many people in the G.O.P. are losing confidence in Bush. A new poll from Iowa, which was released on Thursday, showed the former Florida governor garnering just five per cent of the votes among likely Republican voters. Perhaps the poll, from Quinnipiac University, was an outlier? No, it wasn’t. On Friday, another Iowa survey, this one carried out by the Des Moines Register and Bloomberg Politics, also showed Bush at just five per cent. “By any honest analysis, the first ten months of this year have been a political disaster,” a senior Republican told the Times, adding that it was “an unbelievable position to be twisted into, from ‘shock and awe’ to ‘aw, shucks.’ ”

Why is the Republican pre-race favorite doing so much worse than the Democratic favorite?

The obvious answer is that Bush has had Donald Trump to deal with, and Clinton hasn’t. In virtually monopolizing media coverage and subjecting Bush to months of public criticism, the New York billionaire has transformed the dynamics of the G.O.P. race in a way that almost nobody anticipated—a point the managers of the Bush campaign acknowledged in an internal memo announcing the cost cuts. “We would be less than forthcoming if we said we predicted in June that a reality television star supporting Canadian-style single-payer health care and partial-birth abortion would be leading the G.O.P. primary,” the memo said.

With Bush’s campaign having been outpaced in such outrageous fashion, it is hard not to feel a little sympathy for him. However, his problems can’t be entirely attributed to the Donald. According to the Real Clear Politics poll average, he’s also running behind Ben Carson, Marco Rubio, and Ted Cruz, and nationwide he has the support of just 7.2 per cent of likely Republican voters. For a candidate whose main selling point was supposed to be his electability, these are terrible numbers. On the Democratic side, Clinton, even at the height of concerns about her e-mail server, maintained a healthy lead in the national polls.

In part, Bush’s weak numbers reflect the fact he has run a weak campaign—one dogged by his tendency to mangle the English language, or, at least, to use it carelessly. In his first big speech, back in February, he confused Iran with Iraq and got mixed up about how many fighters the Islamic State has. Since then, the list of phrases he has been forced to clarify or disavow is long and embarrassing: “People need to work longer hours”; “I’m not sure we need half a billion dollars on women’s health-care issues”; “anchor babies”; “stuff happens.” On the basis of what we’ve seen so far, it’s hard to avoid the conclusion that Bush simply isn’t a good communicator. Indeed, he often appears to be a terrible one. Asked on Saturday whether his campaign’s cost-cutting showed it was in crisis, he said, “Blah, blah, blah. That’s my answer: blah, blah, blah.”

If Bush were wowing the world with innovative and substantive policy proposals, his verbal shortcomings could perhaps be overlooked. But he isn’t. His tax-cutting economic plan, which he claims will increase G.D.P. growth to four per cent a year, is largely based on wishful thinking. His foreign-policy speeches are so vague that they’re hard to evaluate. On social issues, such as guns and abortion, he has said little to distinguish himself from the G.O.P. pack. In 2000, his brother George ran on the platform of “compassionate Conservatism,” which was his way of distinguishing himself from Newt Gingrich and other Republican bomb throwers. Jeb’s only memorable slogan is “Jeb!”

Clinton, on the other hand, has made it clear that she is running as a progressive candidate; in the first Democratic debate, she defined herself as “a progressive who believes in getting things done.” To back up this talk, she has rolled out a series of proposals, including paid sick leave, expanded child care for preschoolers, a higher minimum wage, tax breaks for firms that promote employee share ownership, and a series of measures designed to make college more affordable. None of the things she has proposed is particularly radical, but taken together they amount to a concerted effort to tackle wage stagnation and boost the middle class.

Bush has nothing comparable to offer. And, even if he improved as a communicator and Trump dropped out of the race, there would be no assurance that he would win the nomination. Indeed, it now appears possible that his entire campaign is based on two false premises.

The first is that Republican voters want a shift to the center. The one area where Bush has issued a proposal that separates him from other Republican candidates is immigration. To his credit, he has stuck to the position that law-abiding undocumented immigrants should be given the opportunity to obtain U.S. citizenship. About all that has done is win him the enmity of conservative pundits and talk-show hosts, who accuse him of promoting an “amnesty.” On this issue, most Republican voters agree with Rush Limbaugh and Sean Hannity. Polls consistently show that a majority favor the mass deportation of undocumented aliens—an issue Trump has built his candidacy on.

The second shaky premise is the notion that Republicans are keen on restoring the Bush dynasty. From the beginning, this seemed like a dubious proposition: never in its history has America had three Presidents from the same family. When Jeb entered the race, G.O.P. supporters were being asked to embrace the possibility of three Bush Presidents in thirty years.

In its eagerness to promote someone it considered electable, the G.O.P. establishment sought to play down the dynastic aspect of Bush’s candidacy, portraying Jeb as very different from his elder brother: more thoughtful, more conservative, more articulate. Despite these efforts, no groundswell of support emerged for a Bush restoration. Indeed, it now appears that Barbara Bush, Jeb’s mother, spoke for many Republicans when she said, in April, 2013, “There are other people out there that are very qualified, and we’ve had enough Bushes.”