NASHUA, N.H. — One clear winner has emerged so far from the Democratic presidential contest, according to strategists aligned with the president: Donald Trump.

That's the thinking among Republican strategists as Joe Biden's poll numbers have declined in New Hampshire and a two-way race between Bernie Sanders and Pete Buttigieg appeared to emerge ahead of Tuesday's Democratic primary here, yielding what they see as a best-case scenario for Trump.

Trump himself agrees. "If you want to vote for a weak candidate tomorrow, go ahead," he told supporters at a primary eve rally Monday night in Manchester, New Hampshire, suggesting they were free to sabotage the Democratic vote, since his victory in the Republican contest was certain. "Pick one. Pick the weakest one you think. I don't know who that is."

While politicians and political operatives aren't always the best at picking their opponents — Hillary Clinton's campaign was gleeful over the prospect of running against Trump in 2016 — Republicans say they are salivating over the prospect of a head-to-head contest with either Sanders, the independent senator from Vermont, or Buttigieg, the former mayor of South Bend, Indiana.

"In a Bernie Sanders, you have the goofy uncle you try to avoid at the family picnic. In Mayor Pete, you have the tenth guy you add to a conference call when you're hiring a consulting firm," said Jason Miller, a communications strategist for Trump's 2016 campaign. "Neither have the big ideas to go head to head with President Trump."

Privately, campaign advisers acknowledge that Sanders also comes with strengths that could pose a threat were he to be the nominee. He's described by Trump's allies as likable, authentic and consistent — some of the same qualities they believe propelled Trump to victory in 2016. Like Trump, he has also been able to build a movement and an unwavering base of support.

Still, Trump's allies say they see the prospect of a face-off with Sanders as so appealing that they have been making moves to help boost his primary season support. The best scenario for Trump, they say, would be if the Democratic contest continued all the way to the convention, with Sanders battling a candidate backed by the establishment wing of the party.

Trump's advisers are still skeptical of Sanders' odds of winning the Democratic presidential nomination. But even if he does not, they are looking to help fuel divisions within the party in hope that Sanders' supporters will stay home in 2020, or even vote for Trump if they feel the Democratic Party unfairly denied Sanders the nomination.

"If anything, Republicans are trying to prop Bernie up right now, talking about how it is rigged against him," said a person close to the Trump campaign. "I don't even think any Republicans need to say anything for discontent to be stirred up in the Democratic Party, but Republicans are trolling around a little bit, anyway."

Immediately after the meltdown in tabulating the votes from the Iowa caucuses, conservatives, including Donald Trump Jr., were quick to accuse the Democratic Party of conspiring to rob Sanders of a victory.

"OMG. There's nothing the DNC won't do to nuke Bernie… Again. Incredible!" Trump Jr. tweeted. The president himself has repeatedly hit the same theme. "I think they're trying to take it away from Bernie again," he said at his Manchester rally Monday. "I think Bernie came in second. Can you believe it? They're doing it again, Bernie."

Trump's campaign has increased its attacks on Sanders in recent weeks, which a campaign adviser acknowledged could help motivate Sanders supporters. But Trump will likely hold back on his sharpest attacks unless and until Sanders emerges as a nominee.

"Republicans will still attempt to define Bernie as a socialist. They just aren't going at him with the sharpest razor they possibly have," said the person close to the Trump campaign. "They just aren't coming at him with the hard-edge oppo hits yet."

Trump's allies say they are confident that Sanders, a self-described democratic socialist, and his policies won't catch on with swing voters like suburban women, and they question whether he can turn out the black vote in large enough numbers in swing states like Michigan.

"He makes it very easy, and easier than the others, to hold the Dems to account for all of the crazy socialist ideas," Chris Wilson, CEO of WPA Intelligence, who ran the research and digital operations for the presidential bid of Sen. Ted Cruz, R-Texas, in 2016.

Republicans can accuse Sanders of being an "unrepentant socialist who spent his honeymoon in the USSR," Wilson said.

A campaign official said Sen. Elizabeth Warren, D-Mass., who came in third in Iowa, would be a more ideal opponent than Sanders for Trump, because she shares similar policy ideas but doesn't have a similar set of political strengths.

Trump campaign manager Brad Parscale told reporters ahead of Iowa that it "would be an early Christmas present" for Warren to rise to the top of the field.

The candidates the Trump team most expects to face would pose different challenges.

Sanders could reshape the electoral map, forcing Trump to focus on places the campaign had hoped would be locked up but also giving the president an advantage in places the campaign had written off, campaign advisers said. Some recent polls have shown Sanders within striking distance of Trump in traditionally red Texas, for example, and suggested Trump might be neck-and-neck with Sanders in the reliably blue state of Delaware.

A race against Buttigieg would be a more traditional campaign like the one in 2016, with the battle coming down to Rust Belt voters in Michigan, Wisconsin and Pennsylvania.

Trump's allies say they can play up Buttigieg's lack of experience and less moderate views on certain issues. The campaign sent out its first targeted attack on Buttigieg, seizing on comments he had made that it shouldn't be up to the government to draw the line on when a woman can have an abortion.

"Buttigieg's comments confirms his extremist views on abortion, which he would permit without restrictions up until the moment of birth, even for healthy, viable babies," the Trump campaign claimed.

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That's in contrast to Biden, whom the Trump campaign saw as posing the biggest threat based on head-to-head polling, especially in swing states, ahead of the Iowa contest.

If Biden does post strong showings in the contests to come, Trump's allies have their plan of attack already in the works. One group supporting Trump's re-election plans to focus on the foundation Biden started in 2017, hoping to mimic the controversy Republicans sought to stir up around the Clinton Foundation, said a person familiar with the strategy.

Groups are also looking into attacks on business dealings by his brother Frank Biden to paint Biden as a part of the D.C. "swamp," suggesting that, as has been the view of his son Hunter Biden, his family was trying to make money off the Biden name, the person said.

One unknown variable: former New York Mayor Mike Bloomberg. Trump advisers noted that there has been limited head-to-head polling on Trump vs. Bloomberg since Bloomberg began his national ad spending blitz.

But an advantage Trump advisers see to Bloomberg's emergence is the potential for a far longer Democratic primary season that provides ample opportunity to sow further division in the party — setting up the scenario of the socialist vs. the billionaire should Sanders remain in the race, as well.

Regardless of who claims the Democratic nomination, Trump's campaign plans to use the same broad attack to characterize his fall opponent as having policies that would hurt the economy.

"The set of issues the Democrats will run on is knowable now, so it doesn't matter who is carrying the banner," said Tim Murtaugh, the Trump campaign's communications director. "Depending on who it is, there are differences around the edges, like personality — but the policy arguments will be the same."