CHRISTIAN LINDNER, the leader of Germany’s pro-business Free Democratic Party (FDP), is likely to emerge as a crucial figure after the federal election on September 26th. In one of the most open elections the country has known, polling suggests that it will be difficult to form a coalition without the FDP. Among the most divisive figures in German politics, Mr Lindner will relish the chance to cap his rapid ascent with a job in the government—ideally as the next finance minister.

After dabbling in entrepreneurship and serving as an air-force reservist, in 2000 the 21-year-old Mr Lindner became the youngest-ever MP in North Rhine-Westphalia, his home state (and Germany’s biggest). He entered the Bundestag in 2009, and took over the FDP’s leadership four years later, at just 34. He is credited with rebuilding the party’s confidence after a tricky period, in which from 2009 to 2013 it had been an unhappy junior coalition partner to Angela Merkel’s conservative Christian Democratic bloc (CDU/CSU), before falling out of parliament entirely, having failed to cross the 5% electoral threshold at the 2013 election.

This year the FDP (which re-entered the Bundestag in 2017) has staged a modest recovery, benefiting from a collapse in support for the CDU/CSU. It tends to jostle with the hard-right Alternative for Germany (AfD) for fourth place in the polls. The FDP advocates tax cuts, slashing red tape, a hawkish line on public finances and limits to European fiscal integration. More recently, it has pushed for a faster easing of lockdown rules. Its support leans young, wealthy and male. A snappy dresser and charismatic performer who regularly tops “Germany’s hottest politician” lists, Mr Lindner (still only 42) dominates his party to the exclusion of its other talents. He is invariably swarmed by admirers at campaign events.

For decades the FDP was the kingmaker of German politics, propping up coalitions led by the CDU/CSU or the centre-left Social Democrats (SPD). That gave the party outsized influence—between 1949 and 1998 it spent only seven years outside government—and built the careers of influential figures like Hans-Dietrich Genscher, foreign minister for no less than 18 years and one of the architects of German reunification. After the previous election, in 2017, talks to form a “Jamaica” coalition of the CDU/CSU, FDP and Greens (the parties’ colours match the country’s flag) collapsed when Mr Lindner walked out, declaring that it was better not to govern than to govern badly.

Mr Lindner would doubtless like to play kingmaker this year, too. But German politics has become more complicated. The next government will probably need three parties to make up the numbers. It may well come down to a choice between a right-leaning “Jamaica” coalition, with Armin Laschet as chancellor, or an SPD-led “traffic-light” grouping, led by Olaf Scholz. Both would include the FDP and the Greens as junior partners, though they lean in opposite directions.

The FDP would prefer to govern with the CDU/CSU. Mr Lindner knows Mr Laschet well, having worked with him to assemble a CDU-FDP coalition in North Rhine-Westphalia in 2017. But if Jamaica proves impossible, Mr Lindner has signalled that his price for putting Mr Scholz in office would be the finance ministry, a perch from which he would seek to rein in the ambitious spending and investment plans of the SPD and the Greens (and France’s aspirations to deepen euro-zone integration). Many Greens and Social Democrats detest Mr Lindner’s brand of politics, and the feelings are mutual. But from this witches’ brew of resentment and mistrust, a government may have to emerge.

More on the German election:
How do Germany’s elections work?
Why the Greens’ Annalena Baerbock disappointed many
Who is Olaf Scholz, and what kind of Germany would he lead?
Why the CDU/CSU’s Armin Laschet is floundering