Rubio, Cruz have strong performances

Sens. Marco RubioMarco RubioBush ethics lawyer: Congress must tell Trump not to fire Mueller The private alternative to the National Flood Insurance Program  Cruz offers bill to weaken labor board's power MORE (Fla.) and Ted CruzTed CruzCruz offers bill to weaken labor board's power Overnight Finance: GOP offers measure to repeal arbitration rule | Feds fine Exxon M for Russian sanctions violations | Senate panel sticks with 2017 funding levels for budget | Trump tax nominee advances | Trump unveils first reg agenda The Hill's 12:30 Report MORE (Texas) seized leading roles in the Republican presidential debate Tuesday night in Milwaukee, an event that was more substantive than the three previous GOP clashes this cycle but that also offered fewer fireworks.

Both senators have been on the rise in recent polls and seem likely to continue that ascent.

Rubio had strong moments on everything from education to the threat posed by Russian president Vladimir Putin, while also earning at least an honorable draw with Sen. Rand PaulRand PaulOvernight Healthcare: CBO predicts 22M would lose coverage under Senate ObamaCare replacement Fox News personality: GOP healthcare plan says ‘ideology is less important than victory' Rand Paul opens door to backing healthcare bill on key hurdle MORE (Ky.) in an extended, heated exchange about military spending and budgetary prudence. 

“I know that Rand is a committed isolationist. I’m not,” Rubio shot back at one point.

Cruz also interjected in that discussion, saying, to evident approval from the crowd: “You think defending this nation is expensive? Try not defending it.” 

And the Texan also found a creative way to link two common Republican concerns — illegal immigration and the purported liberal bias of the media — when he suggested that coverage of border security would be much different if people entering the United States illegally held “journalism degrees” and were going to drive wages down in the news industry.

The debate, however, had fewer standout moments than any to date. That might have been in part because of the performance of real estate mogul Donald TrumpDonald TrumpDem senator: Pardoning targets of Russia probe would be 'crossing a fundamental line' Trump lawyers looking into special counsel's potential conflicts of interest: reports Trump lawyers asking about presidential pardon powers: report MORE, which was restrained by his standards. Trump did engage in a controversial jab at businesswoman Carly Fiorina, whom he accused of interrupting too much; he also crossed verbal swords with Ohio Gov. John Kasich.

But Trump fell silent for significant stretches of the debate and at other times seemed tentative. Asked about the threat posed by Russia, for example, his answer veered into an insistence that the United States “should have kept the oil” after invading Iraq.

Retired neurosurgeon Ben Carson, who is neck and neck with Trump at the top of the polls, was similarly understated, aside from some early jabs at the media. Carson has been under pressure for days as questions have been raised — unfairly, he says — about elements of his autobiography. 

He started the debate ruling out raising the federal minimum wage, despite indicating earlier this year that he supported such a measure.

Carson’s closing statement also offered a stark departure from the optimism of his rivals, painting a gloomy picture of an America riven by ills including drug addiction and abortion.

The debate also seemed less likely than previous clashes to affect the GOP standings in any meaningful way. That will be welcome news for Trump and Carson, who face no more debates until Dec. 15. Each man has more than twice the support of third-placed Rubio in the RealClearPolitics (RCP) average of national polls, so neither has an incentive to do anything dramatic.

Former Florida Gov. Jeb Bush was much more in need of a game-changing moment on Tuesday evening. He did not appear to get one.

Bush improved upon his soporific showings in the first three debates, delivering an effective early line that mocked Democratic presidential front-runner Hillary ClintonHillary Rodham ClintonDem senator: Pardoning targets of Russia probe would be 'crossing a fundamental line' Trump officials: Russia meddled in the election Trump lawyers asking about presidential pardon powers: report MORE for suggesting President Obama’s economic performance deserved an A grade. 

“It may be the best that Hillary Clinton can do, but it is not the best America can do,” Bush said.

But he was sidelined for long stretches of the debate, and no moment arose that seemed likely to turn around a campaign that has dramatically underperformed expectations.

Paul also imposed himself to a far greater extent than in previous clashes, but whether that matters for a candidate who is drawing only 3 percent support, according to the RCP national average, remains to be seen.

The main debate was also notable for what didn’t happen. In stark contrast to the most recent bout, broadcast by CNBC, there was little contentiousness between the moderators and the candidates. The three co-moderators — Fox Business Network’s Neil Cavuto and Maria Bartiromo, and Gerard Baker of The Wall Street Journal — stuck to neutral but serious questions about the minimum wage, taxation, entitlement reform and small businesses, among other topics.

Trump was also in the firing line much less often than he has been previously. Kasich and Bush both suggested that his plan to deport millions of illegal immigrants was unrealistic. Paul implied that Trump might have mistakenly believed China was among the signatories to the Trans-Pacific Partnership trade deal. 

But the exchanges created a few sparks rather than anything truly explosive.

The same could be said of the debate as a whole. With the Iowa caucuses fewer than 90 days away, the leading contenders will be happy enough with that outcome.