As the Democratic candidates for president pounded each other in a political battle royale in Las Vegas, there was one clear winner: Donald Trump.

"We have not been talking enough about Donald Trump," Senator Amy Klobuchar, the Minnesota moderate, said at one point during the ninth and most combative Democratic debate. A few hundreds of miles away in Phoenix, the president was talking plenty about them.

"We're winning. We're winning like never before. Washington Democrats keep on losing their minds. They hate the fact that we're winning," Mr Trump said to another basketball arena-sized crowd of supporters. "We're winning big. We're winning, winning, winning."

His approval rating certainly suggests he is - despite the chaotic presidency, scandals, high-level ousters and firings, and even being impeached - the president is indeed winning his re-election bout.

Though it's still early in the 2020 cycle, poll numbers suggest, to borrow a version of a phrase coined by former First Lady Michelle Obama, when Democrats go low - on one another - Mr Trump's poll numbers go high, meaning higher.

Donald Trump celebrity president: A decade in two halves Show all 29 1 /29 Donald Trump celebrity president: A decade in two halves Donald Trump celebrity president: A decade in two halves Trump styles his 'You're fired!' pose in his Trump Tower office in June 2012. At the time he was known as a reality TV star on The Apprentice Diane Bondareff/Invision/AP Donald Trump celebrity president: A decade in two halves He was also well known as the patron of the Miss Universe competition Getty Donald Trump celebrity president: A decade in two halves Early signs of Trump's ambition for the presidency can be found everywhere. Not least in his 2011 book 'Time to get tough: Making America #1 again' Getty Donald Trump celebrity president: A decade in two halves Trump with Piers Morgan in November 2010. Piers Morgan has long held that he and Trump are good friends Getty Donald Trump celebrity president: A decade in two halves Trump appeared on Fox & Friends, his favourite show, in August 2011 Getty Donald Trump celebrity president: A decade in two halves Trump considered running in the 2012 election, where he would have faced Barack Obama. He is speaking here at an event for a Republican women's group Getty Donald Trump celebrity president: A decade in two halves Trump was subject to a Comedy Central roast in 2011. He is pictured here being roasted by rapper Snoop Dogg Getty Donald Trump celebrity president: A decade in two halves Given that this Trump store is in the lobby of Trump Tower, it can be said that Trump sells merchandise of himself out of his own home Getty Donald Trump celebrity president: A decade in two halves Trump held meetings with prominent Republicans when considering his 2012 bid. He is pictured here with Alaska governor Sarah Palin Getty Donald Trump celebrity president: A decade in two halves He didn't end up running in 2012 afterall, instead endorsing Republican candidate Mitt Romney AFP/Getty Donald Trump celebrity president: A decade in two halves Trump's golf course in Aberdeen proved controversial in 2012 when he began lobbying the Scottish government against wind power in order that they wouldn't install turbines off the shore by his new course Getty Donald Trump celebrity president: A decade in two halves He even gave evidence to a Scottish parliamentary committee discouraging wind energy AFP/Getty Donald Trump celebrity president: A decade in two halves He still found time for a round of course AFP/Getty Donald Trump celebrity president: A decade in two halves On 16 June 2015, Trump announced that he would run for the presidency of the United States in the 2016 election as a Republican Getty Donald Trump celebrity president: A decade in two halves His campaign was divisive, courting controversy wherever he went. Ultimately he was declared the Republican candidate in June 2016 Getty Donald Trump celebrity president: A decade in two halves Trump took part in the TV debate against opponent Hillary Clinton on 9 October Getty Donald Trump celebrity president: A decade in two halves Trump and wife Melania vote in the presidential election on 8 November 2016 AFP/Getty Donald Trump celebrity president: A decade in two halves Hillary Clinton conceded defeat at 2:50am on 9 November and president-elect Trump swiftly delivered his victory speech to a crowd of supporters Getty Donald Trump celebrity president: A decade in two halves News coverage around the world focused on the huge political upset that Trump's victory spelled AFP/Getty Donald Trump celebrity president: A decade in two halves Trump met with president Obama to discusss transition planning on 10 November. AFP/Getty Donald Trump celebrity president: A decade in two halves Donald Trump and Nigel Farage pose in the golden elevator at Trump Tower on 12 November 2016. Farage was the first British politician to meet with Trump after the election LeaveEUOffical/Twitter Donald Trump celebrity president: A decade in two halves The inauguration of Donald Trump took place on 20 January 2017. Trump's press secretary Sean Spicer boasted that the crowd was the 'largest ever' to witness an inauguration, a claim that was proved not to be true Getty Donald Trump celebrity president: A decade in two halves In his first 100 days as leader, Trump signed 24 executve orders, the most of any president AFP/Getty Donald Trump celebrity president: A decade in two halves One of Trump's most memorable election pledges was to build a wall between the US and Mexico. He is standing here in front of a prototype for a section of the wall Getty Donald Trump celebrity president: A decade in two halves Trump's meetings with other world leaders have provided no short supply of photo opportunities Getty Donald Trump celebrity president: A decade in two halves Trump was welcomed to the UK by the Queen and a state banquet was held at Buckingham Palace in his honour Reuters Donald Trump celebrity president: A decade in two halves Not everyone welcomed the president. Mass protests were held in London throughout his visits in both 2018 and 2019 EPA Donald Trump celebrity president: A decade in two halves One of the most significant meetings Trump has held with another leader was with North Korea's Kim Jong Un. In June 2019, Trump became the first sitting president to set foot in North Korea Getty Donald Trump celebrity president: A decade in two halves 2020 will see president Trump fight for a second term in office, who knows what the next decade will bring? Getty

Gallup, RealClearPolitics and others this week released polling data that put Mr Trump's approval rating near 50 percent - all the figures were either all-time highs for his term or post-impeachment highs.

But instead of trying to slow the president's rise, Democratic candidates were busy jockeying for position by bludgeoning each other with attack lines as the bickered and snapped their way through a raucous debate.

One major reason Mr Trump appears to have won the night were the countless blows former New York Mayor Michael Bloomberg took from his fellow Democrats, as well as his own shaky performance. He appeared unprepared much of the evening, rolling his eyes more often than landing rhetorical blows on his foes.

Coming into the night, Mr Bloomberg was clearly on Mr Trump's mind as the former Big Apple mayor surged in the polls ahead of his debate debut. He mocked him at a water policy event in California earlier in the day as "Mini Mike," a dig at Mr Bloomberg's height.

Like other Democratic candidates, the former Big Apple mayor leads the incumbent in hypothetical head-to-head general election polls - by some margins larger than a poll's margin of error. The president interrupted the event in Bakersfield to tell the crowd that "Mini Mike" harbors "disrespect of the farmer." He was referring to comments his fellow New Yorker made in 2016 about the changing economy that prompted Mr Bloomberg's campaign to fire back, charging the president's policies have hurt farmers financially.

But, to be sure, Mr Bloomberg left Sin City in worse shape politically than when he walked onto the debate stage as the most serious challenger to Senator Bernie Sanders, the Vermont "democratic socialist" who now is the national frontrunner for the party's nomination.

"Democrats take a huge risk if we just substitute one arrogant billionaire for another," said Senator Elizabeth Warren, the Massachusetts progressive who came out swinging at just about everyone on the stage -- but especially the billionaire former mayor.

"So I'd like to talk about who we're running against, a billionaire who calls women 'fat broads' and 'horse-faced lesbians.' And, no, I'm not talking about Donald Trump. I'm talking about Mayor Bloomberg," Ms Warren said in one of the debate's sharpest lines.

"Democrats are not going to win if we have a nominee who has a history of hiding his tax returns, of harassing women, and of supporting racist polls like redlining and stop and frisk," she said before claiming she will "support whoever the Democratic nominee is."

But her assessment of Mr Bloomberg, should he capture the nomination, surely caught the Trump campaign's attention. Any campaigning she would do on his behalf, given her harsh critique likely would seem manufactured to voters.

In fact, the president offered a preview of a likely attack line around the time she uttered that line.

"You know, I came up with the name 'Pocahontas' too early," Mr Trump said, referring to his mocking nickname for Ms Warren, referring to her false statements about a Native American ancestry. "Did you ever see a phony like that? She's a phony."

As the Democratic candidates softened up Mr Bloomberg and sharply criticised one another, Mr Sanders emerged largely unscathed. That means the Democratic Party is on track -- with a long way to go, mind you -- to nominate a self-described socialist just as Mr Trump and his campaign are salivating to run against a far-left Democrat they can paint as a socialist who wants to take money out of Americans' pockets and give it to individuals who seem foreign to them: lower-earning minorities and, according to the president, illegal immigrants.

Democrats intend "to raise your taxes, open your borders, give away free healthcare to illegal immigrants, and ... obliterate your Second Amendment," Mr Trump roared to loud boos.

"Washington Democrats had never been more extreme, taking cues from Crazy Bernie Sanders. How's he doing tonight? One hundred, thirty-two congressional Democrats have signed up for Bernie's health care takeover of the world," Mr Trump warned his supporters. "Think of this: 180 million Americans are going to lose health care coverage under this plan."

Yet, across the desert, Mr Sanders was casting his agenda as the best suited to convince voters to vote Democratic in November and oust Mr Trump. His proposed agenda is one that economic experts, including Democratic economists say would require a dramatic overhaul of the American economy, one that has low unemployment and on which Mr Trump is basing his reelection campaign's message.

"In order to beat Donald Trump, we're going to need the largest voter turnout in the history of the United States. Mr. Bloomberg had policies in New York City of stop-and-frisk which went after African-American and Latino people in an outrageous way. That is not a way you're going to grow voter turnout," Mr Sanders said, going right after Mr Bloomberg, who is trying to cast himself as the lone Democrat who can go right at the brash president and defeat him.

"What our movement is about is bringing working-class people together, black and white and Latino, Native American, Asian American, around an agenda that works for all of us and not just the billionaire class," he said. "And that agenda says that maybe, just maybe, we should join the rest of the industrialized world, guarantee health care to all people as a human right, raise that minimum wage to a living wage of $15 bucks an hour, and have the guts to take on the fossil fuel industry, because their short-term profits are not more important than the future of this planet and the need to combat climate change."

Sanders press secretary slams medical records requests as smear campaign

Meantime, in Phoenix: "While the extreme left has been wasting America's time with the hoaxes," the president said of investigations into his administration and 2016 campaing, "We've been killing terrorists, creating jobs, raising wages, enacting fair trade deals, securing our border and lifting up citizens of every race, color, religion and creed."

With Mr Sanders now the Democrat most likely to face the president, there are few signs the party is ready to unite. Mr Bloomberg, who has tried to wrestle the moderate mantle from others in the field, planted a big seed of doubt about whether the "democratic socialist" can get the job done in November.

"I don't think there's any chance of the senator beating President Trump. You don't start out by saying I've got 160 million people I'm going to take away the insurance plan that they love," Mr Bloomberg said dismissively. "That's just not a way that you go and start building the coalition that the Sanders camp thinks that they can do. I don't think there's any chance whatsoever."