As 2020 looms, everyone is taking Trump’s bid for a second presidential term seriously

Open this photo in gallery:

Hardly anyone took Donald Trump seriously when he rode an escalator down to his Trump Tower lobby four years ago and said he was running for president. When he repeats the campaign-declaration exercise Tuesday in a 20,000-seat arena in Orlando – no downward descent by escalator this time, as the Trump team will take no chances with the metaphor that might prompt – the country, the world and especially his two dozen Democratic campaign rivals will be taking very seriously the man who is the unlikely 45th president of the United States.

It is significant that Mr. Trump’s formal re-election campaign kicks off in the vital State of Florida, for when he took that state on election night 2016 he signalled to heartbroken Democrats that their dreaded nemesis – a twice-divorced Manhattan hotel and casino magnate with a Democratic past and a disrupter future – had transformed the unthinkable into the unavoidable.

Once again Mr. Trump lags in public-opinion polls and in the very public opinions of the American political establishment. But this time he begins his presidential campaign with the symbolic and real advantages of the incumbent:

• A stunning Air Force One jetliner that attracts awe and attention wherever it lands (“The No. 1 perk of being president,” in former president Barack Obama’s estimation);
• The power of the White House “bully pulpit” (the phrase comes from one of his Republican presidential predecessors, the fellow insurgent Theodore Roosevelt);
• The ability to convert campaign notions to national policy with the stroke of a pen or, just as likely, with the signature Trump twist of a tweet (a capacity available to no one else in politics).

Indeed, nine presidents since the Great Depression have been re-elected; only three have failed to win a second term, and each of those three presided over weak economies, a disadvantage Mr. Trump does not possess. Since Franklin Roosevelt’s election in 1932, the party in power has retained the White House for at least eight years with only one exception, when Democrat Jimmy Carter served a single term. (George H.W. Bush also served a single term but that was after eight years of Ronald Reagan; Gerald Ford served after Richard Nixon’s resignation but was not re-elected.)

Those Trump second-term advantages are married with substantial challenges, not least of which is that the President lacks several elements his re-elected predecessors have possessed:

• Personal discipline (Mr. Trump is contemptuous of the conventional political advice he receives from seasoned veterans);
• The authentic support of party leaders (like Mr. Carter, Mr. Trump has surface loyalty from his party but that loyalty is like 19th-century American pioneers’ description of Nebraska’s Platte River, which they had to cross while moving west: broad but shallow); and
• A genuine geopolitical base (Mr. Trump commands the Southern states of the Old Confederacy and some of the traditional Midwestern bloc, but many of the farm states are reeling from his tariffs on agriculture exports and his hold on vital swing states is tentative at best).

A grave danger sign for Mr. Trump: The three most important swing states outside of Ohio, which Republicans traditionally capture if they win the White House, are Pennsylvania, Michigan and Wisconsin. All sided with Mr. Trump in 2016. All elected Democratic governors last year.

These obstacles consume the Trump re-election strategists who sit overlooking the Potomac River on the 14th floor of an office building in Arlington, Va. They face little real opposition in the primary season; Mr. Trump’s only rival for the GOP nomination is former Governor William F. Weld of Massachusetts, who conceded in an interview last week that he expects little support even from Republican officials who harbour grave doubts about the President’s character and his policies.

Instead, Mr. Weld’s potential impact is in legitimizing the Democrats’ view of the President as a lawbreaker with an imperial vision of the presidency that is reminiscent of that of Richard M. Nixon, who left office in 1974 before certain impeachment in the House and conviction in the Senate.

“Nixon faced impeachment because he was vulnerable to charges that he didn’t see that the laws were faithfully executed,” Mr. Weld, who was on the staff of the House impeachment committee in 1974, said in the interview. “Nixon was [an examplar] of the law compared to Trump.”

Mr. Trump waves off such critiques, whether they are delivered by Mr. Weld, by Democrats, or by Representative Justin Amash, the renegade Republican from Grand Rapids, Mich., who last month became the first (and still only) GOP lawmaker to call for the President’s impeachment, an act that prompted Mr. Trump to label Mr. Amash a “total lightweight” and “loser.”

Even so, the President has not had an easy time of it and, despite his breezy clubhouse manner, often seems more beleaguered in office than ennobled by it. Ronald Reagan cited as one of the advantages of the presidency was that “you can invite anyone you want to lunch or dinner, and chances are they’ll come.” Mr. Trump, whose White House invitations have been rebuffed by a series of sports champions, has found otherwise.

And yet, more than any other political figure on the North American scene, Mr. Trump has mastered the manoeuvre of the moment.

A dozen years before Mr. Trump’s emergence as a formidable political force, the American political historian and analyst Thomas Frank, a one-time Republican, wrote in an influential critique of populist conservatism that GOP strategists “have chosen to wage cultural battles where victory is impossible,” the better that “their followers’ feelings of powerlessness will be dramatized and their alienation aggravated.”

That remains the President’s calling card – and the Trump card of contemporary American politics.

But he begins a campaign Tuesday that serves as far more than a test of his appeal for re-election. On trade, environmental legislation, taxes, business regulation, national security and foreign policy, the President’s new campaign is above all the ultimate American test of the endurance of that conception of politics, one that began with an escalator ride on June 16, 2015, and a speech that, in its first minute, said his campaign rivals “sweated like dogs” and in its last sentence vowed to “make America great again.”

Editor’s note: (June 17) An earlier version of this story stated Donald Trump was divorced three times. In fact, he has been divorced twice.

Our Morning Update and Evening Update newsletters are written by Globe editors, giving you a concise summary of the day’s most important headlines. Sign up today.