Berlin - Barack Obama praised Angela Merkel in his memoir for her "unwavering patience" - but as 2021 starts, the German chancellor's patience is set to wear out.

Crucial juncture

Merkel will not stand for re-election in Germany's upcoming national polls, set for September, and her retirement leaves the country's political future wide open at a crucial juncture.

After 16 years in power - spanning three US presidents, four French presidents, five British prime ministers and seven in Italy - Merkel could beat Helmut Kohl as Germany's longest-serving post-war leader, depending on how long coalition talks take next year.

But after all that time, "Merkel's claim to a place in the annals of fame remains oddly inconclusive," argues Constanze Stelzenmueller, a senior fellow at the Brookings Institute.

World's fourth-largest economy

Firstly, there is the 66-year-old chancellor's mixed record on business and the economy.

"The Merkel era saw Germany roar from 'sick man of Europe' to the world's fourth-largest economy, with sharply rising living standards," Stelzenmueller wrote recently.

But "scandals, from 'Dieselgate' to the Wirecard drama, reveal a deeply flawed corporate culture and a resistance to accountability," she said.

And while Merkel's open-door refugee policy at the height of the 2015 may have gained her praise, it propelled the Alternative for Germany (AfD), a once-fringe far-right party, to become the country's biggest opposition force under her watch.

 How long Angela Merkel has been chancellor

CDU must choose a new leader

On the international stage, Merkel's legacy draws on her deft diplomatic skills, as seen at numerous EU and G7 summits.

"Yet she will be equally remembered for her hesitancies and an often maddening incrementalism," Stelzenmueller said.

Still, Merkel could leave on a high note. Her popularity and that of the Christian Democratic Union (CDU) soared during the crisis year of 2020.

But her party cannot rest on its laurels. Before Germany can choose a new leader, the CDU must choose one of its own, and the conservatives' protracted leadership election process - dragged out further by the coronavirus pandemic - threatens to destabilize the party when it should have its eyes on the 2021 prize.

Annegret Kramp-Karrenbauer, German defence minister, currently serves as CDU leader, after Merkel anointed her as successor back in 2018 - but AKK, as she is known, announced in February that she wouldn't run for the chancellery and vowed to hand over the party reins to someone who would.

Three contenders

To what extent Germany's Christian Democrats will remain the centrist party of Angela Merkel even after she is gone depends on who is elected to lead it into the 2021 elections.

The three contenders to replace Kramp-Karrenbauer are: Friedrich Merz, a lawyer and wealthy businessperson; Armin Laschet, the premier of North Rhine Westphalia, Germany's most-populous state; and Norbert Roettgen, a foreign policy expert who has vouched for closer US ties while holding Russia at arm's length.

Supporters of Merz, the most right-wing of the three, have claimed that he could win back voters the CDU has lost to the AfD.

Laschet, on the other hand, is considered to be Merkel's preferred pick and would be expected to deliver more of the same for the centre-right party.

Party conferences scheduled to elect a leader have twice fallen victim to the pandemic: first in April, followed by another cancellation of the December event.

The latest postponement "has reopened old wounds within the party and shaken its self-confidence," said Alexander Privitera, head of European Affairs at Commerzbank.

Merz lashed out at the delay, claiming that it was part of efforts by the "party establishment" to keep him from taking the reins.

Kramp-Karrenbauer rubbished his criticism as a conspiracy theory.

Crucial party conference

A new date for the crucial party conference has been set for January 16, but it won't be the usual in-person gathering of the CDU's 1,001 delegates.

Instead, the leadership election is to take place online and be later ratified in a postal vote, in order to get around German laws which ban a political party from electing its leader entirely online.

Even with the CDU vote done, the future party leader might be pipped at the post to become the chancellor candidate, given that any decision must be made together with the CDU's regional sister party, the Christian Social Union.

CSU leader Markus Soeder has been tipped as a potential contender for the top job in German politics, and has been using the pandemic to hone his profile far beyond his home state of Bavaria.

Meanwhile, Health Minister Jens Spahn's rising star during the coronavirus crisis has led to speculation that he might throw his hat in the ring at the last minute for the CDU leadership.

"He appeals to the conservatives — he comes from yearlong (sic) experience in the Finance Ministry ... — as well as progressives, since he is openly gay," Privitera wrote in a recent blog post.

Either way, life without Merkel still seems a long way off, as she continues to wield influence in the pandemic, including at EU level, having played a key role in the bloc's response to looming recessions.

"While under normal circumstances a chancellor in her last year of office would slowly turn into a lame duck, there is still no sign that this will be the case with her. On the contrary, both domestically as well as internationally, she is making her full presence felt," Privitera said.

"The next general election in the fall of 2021 still feels very far away indeed."