WASHINGTON — President Donald Trump's barnstorming tour for the midterm elections has generally been about as subtle as, well, a Make America Great Again rally.

The formula is simple: hold a raucous stump session with thousands of die-hards in a mid-sized arena; tear into Democrats, the news media and the "witch hunt" federal investigation run by special counsel Robert Mueller; and churn out political red meat about the border wall, professional athletes who kneel during the national anthem and whichever celebrity or politician he's feuding with at the moment.

But Republicans are nervous about potential Democratic pickups after a series of special elections in which Democrats have outperformed, culminating in a photo finish in a classically Republican suburban-exurban Ohio district last week — and so Trump and his aides are getting more creative about how best to deploy him in places where his presence threatens to hurt more than it helps.

On Monday, as he provided aid to New York Republican Reps. Elise Stefanik and Claudia Tenney — as well as Arizona GOP Rep. Martha McSally — Trump applied a much softer political touch by orchestrating a bill-signing ceremony at Fort Drum and a fundraising reception at a DoubleTree hotel in Utica, N.Y.

The clear aim: support Republicans without alienating swing voters or further inflaming Democrats.

Trump's choice of venues makes good political sense on competitive turf in a blue state, according to former New York Rep. Steve Israel, who ran the Democratic Congressional Campaign Committee for two election cycles.

"He's like the inflatable air dancer in front of the used car lot — he attracts a lot of attention but can turn off a lot of voters," Israel said in an e-mail. "His rallies appeal to his base, energize the opposition, and risk losing moderate voters in swing districts when he says crazy things. So in moderate districts in New York, both with recent histories of electing Democrats, you don’t want a retail Trump event."

There’s nothing unusual about a president using a more full complement of political events to help lawmakers in his own party, involving a similar set of political calculations. George W. Bush and Barack Obama knew there were certain districts and states where they were only popular with a targeted audience. Still, Trump usually prefers the MAGA rallies, which are more about him and his re-election campaign than the candidates he is trying to assist.

Whether Trump pulls out all the stops with a MAGA rally or quietly records a robocall endorsement for a candidate depends on the race, National Republican Congressional Committe spokesman Matt Gorman told NBC earlier this year.

“There’s no one-size-fits all approach," he said.

Now Trump is starting to use all those tools.

Of the candidates in close races on turf Trump visited Monday, Tenney is more clearly at risk of losing her race in a district where the GOP has been badly divided between its Tea Party and establishment wings. The Cook Political Report rates her matchup with Democrat Anthony Brindisi as a toss-up, and Brindisi had more cash on hand at the end of the last fundraising quarter — $1.4 million to $1 million.

Stefanik's district, which covers the northeastern reaches of the state, has a more Democratic tilt, having favored Obama twice before going for Trump in 2016. But her opponent, Tedra Cobb, has struggled to gain traction and was hurt by a video showing her telling a voter she supported a ban on assault weapons but would lose the race if she espoused that view publicly.

Stefanik wanted Trump to come to her district, but not for a rally. Rather than endorsing the local congresswoman to a crowd of amped-up Trump voters, he thanked her, before a uniformed audience of troops, for persistently asking him to come to the base.

"She didn't stop, and here I am," he said.

The nonpartisan message: Stefanik is not only fighting for the troops based in her district but has the clout to bring the president to town.

While he was there, delivering a modified stump speech that omitted his most highly charged political rhetoric, Trump also gave a nod to McSally, who is locked in a tough three-way primary for the seat held by retiring GOP Sen. Jeff Flake.

"There's another member of Congress here today who is not only an Air Force veteran, but the first woman to fly a fighter jet in combat in U.S. history," he said. "She is terrific. ... Thank you, Martha, Thank you for being here."

The deft nod, which McSally can certainly use in her campaign, comes in the stretch run before her Aug. 28 primary against former State Sen. Kelli Ward and former Sheriff Joe Arpaio, whom Trump pardoned earlier this year. Despite pressure from other Republicans, Trump has steadfastly refused to make an endorsement in the primary in a state that he won by just 3 points in 2016.

But the kind words for McSally against the military backdrop might be better for her as she tries to navigate through the primary and a general election against Democratic Rep. Kyrsten Sinema.

At the fundraiser for Tenney, he lauded the congresswoman for having "done so much for us" on Capitol Hill. "Hopefully we put Claudia right over the top where she belongs."

But while he slammed Gov. Andrew Cuomo, a Democrat, for New York's tax rates and incited a brief "lock her up" chant by mentioning Hillary Clinton, he generally stayed away from his favorite partisan boogeymen.

Former Virginia Rep. Tom Davis, who once headed the National Republican Congressional Committee, said before the events that Trump had found ways to give assistance without needlessly agitating already energized Democrats.

"The Republicans' biggest obstacle right now is the enthusiasm gap," he said in an email exchange with NBC News. "The D[emocratic] base is already fired up. Trump-centric voters are not. Also, he is very helpful for raising money. This will be net pluses in these two districts."