Washington ? Propelled by her husband’s post-White House earnings, Sen. Hillary Clinton’s average net worth soared from red ink to $30.7 million between 2000 and 2006, the fastest financial climb among members of Congress who arrived without assets, a watchdog group reported Tuesday.

Arizona Sen. John McCain, the presumptive Republican presidential nominee, reported a $27.6 million surge in his and his wife’s average worth from 1995 to 2006. Their worth rose over that 11-year period from an inflation-adjusted average of $8.9 million to $36.4 million, the ninth-biggest rise in Congress, the nonpartisan Sunlight Foundation reported.

Because lawmakers are allowed to list their assets in wide ranges and exclude homes that can be worth millions of dollars, the foundation acknowledged that the data may create misimpressions.

Democratic presidential front-runner Barack Obama’s average net worth rose from $328,442 in 2004 to $799,006 in 2006. But counting Obama’s pricey Chicago home, he almost assuredly has joined the Senate’s “Millionaire’s Club.”

The wealthiest member of Congress is Rep. Jane Harman, D-Calif., at $409.4 million.