Real-money fantasy sports site FanDuel is seriously considering a new fundraising round that would value the company at $1 billion or more, Fortune has learned from multiple sources.

This comes just five months after the New York-based company raised $70 million from an investor group that included Shamrock Capital Group, Kohlberg Kravis Roberts & Co. KKR , NBC Sports Ventures and prior backers like Comcast Ventures. No valuation was publicly disclosed for that round, but one source familiar with the situation says that the post-money valuation was south of $400 million.

Boston-based rival DraftKings had previously raised $41 million at a post-money valuation of less than $250 million.

FanDuel’s board of directors has not yet approved a new stock sale, but is talking about a round that likely would add at least another $100 million to the company’s coffers. The goal would be to accelerate customer acquisition and pro sports partnership efforts, with an eye toward going public in 2016.

A FanDuel spokeswoman declined to comment. The company focuses on one-day games (as opposed to season-long leagues), and says that it has pays out around $10 million in winnings per day.

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