(FORTUNE Magazine) – If John Kerry is elected, he and wife Teresa--heiress to the Heinz ketchup fortune--would reportedly be the richest First Couple ever (one estimate pegs their combined wealth at more than $1 billion). But if you measure just individual net worth, Lyndon Johnson, who made a fortune in Texas real estate, would rank as the richest of the past eight Presidents. Granted, measuring presidential wealth is more art than science. In the 1960s and '70s some candidates started volunteering financial information, and since 1978, Presidents have been required to disclose income-generating assets. But they're allowed to give a wide range for asset values and aren't required to include fortunes that are tied up in family trusts or nonliquid assets like personal residences. For instance, George H.W. Bush's then-- $2.2 million Kennebunkport estate isn't included, but George W.'s ranch, which makes some money from agriculture, is.

Kerry's 2003 Senate disclosure form listed his net wealth as between $667,000 and $2.5 million (we've used the midpoint), the biggest chunks coming from the money he received from his mother's estate and a $300,000 painting. But even blue-bloods borrow: Kerry took out a $6.4 million loan against his half of the value of the couple's Boston townhouse to help foot the bill for his campaign. Here's a snapshot of what he and each of the past eight Presidents were worth (we used the number available closest to the time each held office, and adjusted for inflation). --Telis Demos