BERLIN — When Mrs Angela Merkel was wrapping up a speech at an election rally last week in the picturesque university town of Heidelberg, two tomatoes were thrown at her.

One missed the German chancellor, the other grazed her but barely left a mark. Mrs Merkel said nothing to the crowd — she simply brushed down the bright red outfit she was wearing. A few hours later, she appeared in the same clothes at another rally.

The incident is typical of the chancellor’s softly-softly approach in her bid for a fourth term in office. Her critics call it a “sleep campaign”, but the election’s dullness serves the 63-year-old chancellor well — barring an extreme shock, she seems likely to win on September 24.

While the world has grown accustomed to electoral surprises, with the United Kingdom’s Brexit vote and United States President Donald Trump’s election, mainstream pollsters all predict another comfortable victory for her conservative bloc.

She seems likely to cement her position as Germany’s unrivalled leader, the European Union’s top politician and a force for international co-operation in a world buffeted by political crises and a surge in nationalism, not least in Mr Trump’s America-first White House.

“The Germans see an uncertain world and don’t want to change their captain in a storm,” says Mr Helmut Jung, consultant at the GMS polling agency.

The relative comfort of her fourth election campaign is even more surprising given the position she faced a year ago.

At the time, Mrs Merkel was still reeling from the 2015-16 refugee crisis, in which more than one million asylum seekers arrived as she controversially kept Germany’s borders open. Her crisis management record — acquired in the global financial upheaval, the Greece bailouts and the Ukraine conflict — was battered, as was her image as the nation’s mother.

The old alliance between Mrs Merkel’s Christian Democratic Union (CDU) and its more conservative Bavarian ally, the Christian Social Union, was at breaking point. The low point came in October last year, when the chancellor was disrupted by rightwing demonstrators at a ceremony in Dresden marking the anniversary of reunification with shouts of “Merkel must go.”

When Mr Martin Schulz won the race early this year to lead the Social Democrats, sending the party’s support soaring in the polls, Mrs Merkel braced herself for “the hardest election campaign I have ever fought”.

Yet her recovery has come at a cost.

Even if the “sleep campaign” has voters backing Mrs Merkel, it will be with less enthusiasm than before. The refugee inflows have shaken up politics. The voters’ trust no longer runs so deep, especially among conservatives worried about immigration.

“In the last election in 2013 she was a presidential chancellor, standing above the parties. Now she is a chancellor who divides opinion,” says Hermann Binkert, head of the Insa polling agency.

MERKEL’S AURA HAS dimmed

In the past year, Mrs Merkel has executed a dramatic turnround.

First, the effects of measures to reduce refugee inflows have taken effect, including a controversial Berlin–backed EU migrant deal with Turkey. She insists that welcoming asylum seekers in the summer of 2015 was the right response in “a humanitarian emergency”. But she pledges it “cannot and must not be repeated”.

Most Germans have decided to give her the benefit of the doubt.

Next, while Mr Trump’s election has caused her many headaches, it has had the unexpected benefit of scaring Germans into rallying around her.

As a CDU official says: “We can send a thank you every month, every week, every day to Washington.”

Mr Schulz has also failed to deliver. His rapid ascent in the polls has been followed by a quick descent, which leaves the Social Democratic Party (SPD) almost where it was before he started, at its post-1945 nadir.

As in previous elections, Mrs Merkel has concentrated on vaguely defined but important positives: Economic wellbeing, low unemployment, social stability and EU co-operation.

The CDU’s main slogan is “For a Germany in which we live well and happily”.

Mrs Merkel avoids attacking the opposition, whether Mr Schulz or the anti-immigration Alternative for Germany, which threatens to become the first big right wing party in Parliament since World War II.

Analysts call it “asymmetric demobilisation” — by reassuring her own supporters she wants to demotivate her opponents. She has also played down controversial issues.

In campaign speeches, her main point on refugees is to thank the millions who volunteered to help the newcomers.

On the diesel emissions scandal that harmed the German car industry and led to billion-dollar fines, she balances criticism of the industry executives over cheating on tests with support for an industry employing 800,000 and consideration for the 15 million Germans with diesel cars.

The soft approach is deliberate. Asked at a press conference last month why her campaign was so boring, she answered that her campaigning was not about “insulting each other” but about explaining party programmes to people.

“There are always people who want to hear this. For me, that is not boring but exciting and interesting.”

As in previous elections, she has targeted centrist voters, stealing shamelessly from the Social Democrats, for example, in claiming credit for the legal minimum wage, an SPD policy she originally opposed.

This may disappoint right-wingers, prompting some to stay at home and others to vote Alternative for Germany (AfD). But it works because elections are won in the centre, especially in Germany.

According to a Bertelsmann Foundation study, 80 per cent of Germans see themselves in the political middle, well above the EU average of 66 per cent. Mrs Merkel’s bloc stands on about 38 per cent in the polls, well clear of the SPD on about 22 per cent, and close to the 41 per cent it won in 2013.

Four smaller parties likely to reach the Bundestag are polling seven to 10 per cent — Die Linke (the Left), the Greens, the AfD and the liberal Free Democrats. But some of Mrs Merkel’s invincibility aura has gone. In Heidelberg, a wealthy, CDU-voting town, her speech was accompanied by whistles from AfD supporters.

While numbering perhaps only 50 in a crowd of more than 2,000, their shouts of “Merkel must go” filled the square. Nearby were other demonstrators protesting against the diesel scandal.

Equally striking was the subdued mood among CDU loyalists. Some said her speech lacked specifics — a complaint heard at other rallies.

“She isn’t really saying much,” said one CDU voter. “She is only speaking about the world and not about Germany,” added another.

Mr Wilfried Kratz, a pensioner, said the refugee crisis had “unsettled” people. “They are polite, but they are not entirely satisfied.”

This undertone of dissatisfaction goes beyond Heidelberg. The only one-to-one television debate between Mrs Merkel and Mr Schulz ended with opinion polls showing a clear win for the chancellor: 55 per cent found her convincing, against 35 per cent for Mr Schulz. But commentators bemoaned a lack of disagreement between the leaders.

TV presenter Thomas Gottschalk said: “They were both always nodding their heads when the other was speaking.”

For conservatives, the refugee question is only one of a string of policies in which Mrs Merkel has swung too far to the left. They complain about everything from the end of conscription in 2011 to the Bundestag voting to legalise gay marriage this summer.

NO BIG SHIFTS ON FOREIGN POLICY EXPECTED

One sign of the right’s disenchantment is the AfD’s rise. Another is a sense that after 12 years of Mrs Merkel, Germany needs a new leader.

Mr Karl-Theodor zu Guttenberg, 45, a former rising star of the CSU, received a huge welcome for a speech that marked his return after six years out of politics.

The conservative Bavarian aristocrat, once seen as a potential chancellor, resigned as defence minister in 2011 over a doctorate plagiarism scandal. His comeback was greeted by more than 1,000 fans in his hometown.

Bild newspaper put Mr zu Guttenberg and his wife on its front page with the headline: “The return of the Guttenbergs”. But for now, Mrs Merkel still rules the roost.

If she wins, her priority will be forming a coalition. Assuming the polls are right, she would secure the biggest majority by sticking with the SPD.

Mr Jurgen Falter, politics professor at Mainz University, says: “The respect which she and Mr Schulz showed each other in the television debate suggests that another grand coalition is very likely.”

However, many SPD activists fear that another deal with Mrs Merkel would hurt their hopes of political revival. Her ideal coalition partner could be the Free Democrats, who look well set to return to the Bundestag, although the party is unlikely to secure enough votes for a two-party coalition.

She could try to involve the Greens, but Prof Falter says the chancellor would probably not risk Berlin’s first, and possibly unstable, three-way coalition.

In any event, Germany’s foreign partners should not expect big shifts.

The Social Democrats, Greens and FDP all support Mrs Merkel’s policies on the EU, North Atlantic Treaty Organisation and international co-operation. Like her, they subordinate their distaste for Mr Trump to the need to work with the EU’s strongest ally.

And all plan to co-operate with French President Emmanuel Macron on reviving the EU. There are subtle differences, over defence spending and eurozone integration. But Mrs Merkel would still call the shots, as she is well placed to control the most Bundestag votes: The CDU/CSU is likely to hold at least 70 per cent of the seats in any coalition.

Moreover, despite their misgivings, most CDU/CSU voters desire some form of continuity. As Mr Gabriel Steinmuller, a student at the Heidelberg rally, said: “We should not try any experiments. We are doing so well in Germany. Let’s keep things as they are.” FINANCIAL TIMES