Counting Mitt's millions

How rich is Mitt Romney? A few different answers, in increasing order:

Last Monday, the campaign announced: "Governor and Mrs. Romney's assets are valued between $95 and $287 million."

In subsequent news reports, the campaign said the Romneys "hold assets worth between $190 million and $250 million."

Steve and Cokie Roberts evidently added in Romney's sons' trusts and wrote: "His immediate family owns trusts worth as much as $350 million."

The biggest numbers attached to Romney's name predate these reports. In his book A Mormon in the White House? 10 Things Every American Should Know About Mitt Romney, Hugh Hewitt writes:

"The chairman of the Massachusetts State Democratic Party, Phil Johnston, pegged Mitt Romney's net worth as between $500 million and $600 million in an interview he gave to MSNBC. . . . And Johnston may have missed by a factor of 100 percent the true size of Romney's holdings, which many observers estimate in excess of a billion dollars.

"A half billion or a billion, it doesn't really matter. If elected, Mitt Romney would be the wealthiest president in American history -- by a lot."