The question has been asked many times recently, and for good reason: Who is Mikhail Prokhorov?

Born in 1965, he is the Russian entrepreneur and billionaire who owns the NBA franchise the New Jersey Nets. But more importantly, perhaps, what has thrust him into the global limelight is his decision to challenge Russian Prime Minister Vladimir V. Putin for the country's presidency. The third richest man in Russia made his money in precious metals but he wants to leave his legacy in politics.

I made a decision, probably the most serious decision in my life: I am going to the presidential election, said Mr. Prohkorov, at a news conference.

Prokhorov hasn't been too visible in public lately after he ws removed as head of Russia's pro-business party Just Cause in mid-September after disagreements with Kremlin strategists. Now, however, he thinks the time is right to return to the public forefront.

You may remember, the Kremlin removed me and my allies from Just Cause, and we were not allowed to do what we wanted, Prokhorov said. It is not in my nature to stop halfway. So for the last two and a half months we sat and worked, very calmly and quietly, and we created all the infrastructure to collect two million signatures (the number needed to get on the ballot as an independent candidate).

Writes the Washington Post: Prokhorov has been cautious not to cross Putin's path in the past and has even been called a Putin puppet, but may pose a serious challenge to Putin, whose authority has been dented by the Dec. 4 parliamentary elections and massive street protests against alleged vote fraud. 

Born in Moscow, Prokhorov is said to have a net worth of $18 -- enough to make him the 39th richest man in the world in 2011 according to Forbes. 

After graduating in finance from a Russian university in 1989 -- the Moscow Finance Institute -- Prokhorov, who stands six-foot-8, quickly found success with Norilsk Nickel, en route to amassing a fortune through ownership in various precious metals companies. In September 2009 he made an offer to buy controlling interest in the NBA's Nets, and in May 2010 the NBA approved the sale. He became the team's majority owner with an 80 percent stake an a 45 percent interest in the team's new home, Barclays Center.