BERLIN (Reuters) - German Chancellor Angela Merkel praised her veteran finance minister at a party in his honor on Monday, as a potential coalition partner laid claim to his job as their price for supporting her in power.

German Chancellor Angela Merkel, European Commission President Jean-Claude Juncker and German Finance Minister Wolfgang Schaeuble pose for a photograph as they attend a gala reception organised by the CDU in Baden-Wuerttemberg to mark Schaeuble's 75th birthday in Offenburg, Germany, September 18, 2017. REUTERS/Kai Pfaffenbach

Speaking at Wolfgang Schaeuble’s 75th birthday celebration, Merkel paid tribute to his 45 years as a member of parliament, but gave no clear signal that she wanted to retain him in the post after a national election on Sunday that she is on track to win.

“We’re fighting together at the moment to ensure there are at least four more years,” Merkel told attendees at the event hosted by her Christian Democrats (CDU) in Offenburg, in his constituency in the southwestern state of Baden-Wuerttemberg.

In a wheelchair since a deranged man shot him at an election campaign event a few days after German reunification in 1990, Schaeuble lives for his job and has made abundantly clear he would relish another run as finance minister.

But his fate may rest in the hands of the parties Merkel ends up governing with. On Monday, the pro-business Free Democrats (FDP), regarded as a natural ally of her conservatives, made a play for his ministry in exchange for joining the next coalition.

“The FDP should enter no government in which it cannot name a finance minister,” Alexander Hahn, a member of the party’s national executive, told mass-market daily Bild.

The FDP is still haunted by its decision not to take the finance ministry in 2009 at the start of Merkel’s second term - a move that backfired as Schaeuble quashed the FDP’s plans for tax cuts, alienating its pro-business supporters who then booted it out of parliament in 2013.

The FDP has reinvented itself with a hard line on Europe and its leader has voiced concerns that Merkel and French President Emmanuel Macron plan to strengthen the euro zone by creating a system of financial transfers between states.

Schaeuble, who is the face of German austerity and has insisted that EU countries adhere to Europe’s budget rules, could help Merkel keep conservative voters and lawmakers on board as they press ahead with deeper euro zone integration.

“MANY HEARTFELT THANKS”

Horst Seehofer, leader of Merkel’s Bavarian sister party, the Christian Social Union (CSU), said he favoured a tie-up with the FDP.

“I quite clearly hope for a black-yellow coalition,” he told the Handelsblatt daily referring to the parties’ colors.

The FDP is currently polling well above the 5 percent threshold it will have to cross to re-enter parliament on Sunday, but surveys suggest it and Merkel’s conservatives will probably need a third partner to secure a majority.

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The chancellor may yet find herself resuming the current grand coalition with the center-left Social Democrats (SPD), whose leader Martin Schulz accused her of personally blocking measures proposed by his party to improve the situation of families with small and medium incomes.

During a town hall-style ARD television interview, he said Merkel would start to roll back social policy reforms after the election if she was able to form a conservatives/FDP coalition.

“They want to abolish the law to limit rent increases. And then the property market will go through the roof,” he said.

The far-right Alternative for Germany (AfD), which is expected to enter parliament for the first time, meanwhile beefed up its anti-immigration rhetoric.

“Germany has become a safe haven for criminals and terrorists from all over the world because thanks to a lack of border checks it’s easy to get in,” top AfD candidate Alice Weidel said in Berlin.

Merkel, who was dressed in the conservatives’ black and the FDP’s yellow, paid tribute to Schaeuble as a European, a fighter for German unity, a passionate parliamentarian and an intellectual force who kept calm in hectic situations.

But she also wished him time to spend with his family and try out new things, as she presented him with the complete works of Dietrich Bonhoeffer, a German pastor and theologian known for his opposition to the Nazis.

“We wish you a good read, new insights, all the best and, in the name of the CDU and from me personally, dear Wolfgang Schaeuble, many heartfelt thanks,” Merkel said.