The battle for Fisker pits Hybrid Tech, led by Richard Li, the son of Hong Kong's richest man, Li Ka-shing, against Wanxiang, China's largest auto-parts supplier.

Wanxiang is the owner of B456 Systems Inc, the successor to A123 Systems Inc, the US company that supplied batteries to Fisker until collapsing under the cost of recalling defective Karma power packs. It would make sense for Wanxiang to buy Fisker after acquiring the battery-maker, said Shifley.

The Karma was designed by Henrik Fisker, who won plaudits for his work on cars for Bayerische Motoren Werke AG (BMW) and Ford Motor Co's Aston Martin. Karma drivers included singer Justin Bieber and actor Leonardo DiCaprio.

Fisker was an early partner of Tesla Motors Inc, which accused it of stealing technology and designs intended for what became the Tesla Model S. Fisker prevailed.

With the car still in the design stages, Fisker in 2009 won the largest loan commitment to a startup company from a US Energy Department program to develop alternative-fuel vehicles. Most of the $529 million was predicated on Fisker manufacturing cars in the US.

That didn't happen. Fisker failed to meet production milestones for the Karma, which was made in Finland. The Energy Department froze the loan after distributing $193 million.

For all its low-slung curb appeal, the Karma was plagued by technical flaws. Consumer Reports said its review model broke down after going fewer than 200 miles. The cars were recalled three times for battery and cooling-fan defects before A123 stopped production.

Last April, after firing most of its workers, Fisker defaulted on the US loan without making a payment.

Li's Hybrid Tech last year paid the Energy Department $25 million - about 15 percent of the balance - to assume ownership of the loan, putting Hybrid in a favorable position to take over Fisker's remains. The department sold the loan to salvage what it could from the money Fisker had drawn down.

Fisker filed for bankruptcy protection in November under an arrangement calling for the group led by Li to trade its ownership of the loan for the automaker's assets.

That plan was derailed in December, when Wanxiang told the court it wanted to bid.

Hybrid's latest bid was $55 million, including the $25 million it invested in the US loan. Wanxiang has offered $35.8 million in cash, up $10 million from its first offer.

The duel is being watched in Wilmington, Delaware, where Fisker spent $20 million in 2010 to buy the abandoned GM plant. The plan was to retrofit it to build a second model, to be called the Atlantic, with production targets as high as 100,000 cars a year. Delaware taxpayers are footing the electricity bill for the plant until its future is decided.