Donald Trump’s re-election campaign is well under way with a dark advert featuring dramatic music and a brutally simple message: “He’s no Mr Nice Guy.”

The commercial boasts the president is “changing Washington”, uses dubious statistics to tout his record on the economy and immigration and goes on the offensive against Democrats.

However, the ad has been greeted mostly with grudging praise even from some Democrats as an effective harbinger of the likely message Trump’s campaign will hone in the coming 2020 presidential election.

David Plouffe, former campaign manager for Barack Obama, tweeted: “Donald Trump ad that just ran during World Series was quite strong. National TV ads in October of off year – unprecedented.”

Michael Cornfield, an associate professor of political management at George Washington University, added: “Men of action don’t have time for niceties like facts and rules. And neither do 30-second ads. Effective angle for any incumbent – even this one.”

The ad is hardly subtle.

“Obliterating Isis,” says a male narrator, as the commercial shows an already famous photo of Trump as commander-in-chief, with the vice-president, Mike Pence, and his national security team, in the situation room watching the raid that killed the group’s leader, Abu Bakr al-Baghdadi.

This is followed by footage of military explosions and a picture of Baghdadi being crossed out in red. There is a swipe to the House speaker, Nancy Pelosi, who is masterminding the impeachment inquiry against Trump, followed by Adam Schiff, chair of the House intelligence committee, and former special counsel Robert Mueller – all set to be portrayed as villains in the campaign narrative.

The narrator continues: “Their caliphate destroyed. Their terrorist leader dead. But the Democrats would rather focus on impeachment and phony investigations, ignoring the real issues. But that’s not stopping Donald Trump.”

It adds: “He’s no Mr Nice Guy, but sometimes it takes a Donald Trump to change Washington.”

The final line could be seen as a nod to those conservatives who say they are not always fans of Trump’s style, especially his use of Twitter, but who embrace his policy agenda. It also recognises Trump’s popularity among a base who complained that politicians were all the same until his insurgent candidacy.

Democrats responded with a fact check: “CLAIM: Trump created 6 million new jobs. THE TRUTH: that’s a million fewer jobs than President Obama created during the equivalent time period.”

It concluded: “CLAIM: Trump’s no Mr Nice Guy. THE TRUTH: they can have this one.”

The Trump campaign reportedly spent a seven-figure sum to run the ad during the deciding game of baseball’s World Series on Wednesday night – more than a year before election day.

The commercial is based on a previous ad but has been updated to include the killing of Baghdadi. CNN reported that Trump’s campaign manager, Brad Parscale, said it was made the same day it aired. Baseball fans watching a big screen at the Washington Nationals’ stadium on Wednesday reportedly greeted it with boos.