German Chancellor Angela Merkel has sat at the helm of Germany's government for a staggering 16 years, putting her in the driving seat for most of Germany's 21st-century development. But her time in office comes to an end this month as her fourth and final term ends. The vacuum her party left has opened a window, one a party to the German left hopes to fill.

       The CDU is a liberal-conservative Christian party that has captured German politics for nearly two decades.

       Ms Merkel's popularity and reputation as a de facto EU leader has carried it ahead of her primary opponents - the Social Democratic Party of Germany (SPD).

       The upcoming German election on September 25 will put them head-to-head once again.

       And this time, it appears the left-wing SDP has a chance to come out on top.

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       The SDP sprung from the 19th century General German Workers' Association and currently holds an explicitly socialist platform.

       As of September 9, 2021, the SDP is polling ahead of the CDU.

       Politico's Poll of Polls for this year's elections gives the party a four-point edge, with a prospective vote share of 25 percent to the CDU's 21 percent.

       Political experts believe the party could join forces with the German Greens and form a ruling coalition.

       The current Chancellor is among them, and she spent what was potentially her last appearance at the Bundestag pleading for voters to back her successor.

       She said Germans could choose between one of two coalitions to take Germany through the next four years.

       Ms Merkel said a CDU-led coalition with the Christian Social Union (CSU) would lead Germany "into the future with moderation", while the SPD-Greens alliance would lean on cooperation with the Left or "at least don’t rule it out".

       The Left is another German party currently polling in dead last with a prospective six percent of votes.

       The SDP appears to have a real chance of winning, at present, and offers a Merkel-esque Chancellor via their candidate, centrist Olaf Scholz.

       Mr Scholz is Germany's Vice-Chancellor, and his party chose him to represent the SDP on August 10.

       Since then, the party has pulled out ahead of the CDU polling-wise.

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       On August 10, the party was six points short of the CDU's 25 percent on 19, and within the month, it had taken that 25 percent of support for itself.

       Should it win the election, the SDP has one of two paths to power.

       The party's first option is the one Ms Merkel laid out, a three-way pact between the SDP, Greens and Left.

       But they could also go another direction and ally with the Greens and conservative Free Democrats.

       Otherwise known as the FDP, the pro-business party is currently polling at 12 percent.

       Parties require more than half of the 598 to install a Chancellor of their choosing.

       The coalition Ms Merkel warned about would give the SDP fewer seats.

       If the SDP won and combined their prospective 218 seats with the Left's 52 and Green's 148, they would have 418.

       The latter coalition would bring a prospective seat share of 479 seats in total, the highest of the two options.