Joe Biden’s running mate Kamala Harris,announced on August 11, already stands out on the political field as the first woman of color on a presidential campaign ticket. Another factor sets the California senator apart: She is among the wealthiest of the Democratic candidates for the 2020 election.

Biden chose Harris as his potential Vice President after they campaigned against each other during the Democratic primary—with former VP Biden ultimately prevailing over rivals to be presumed the party’s nominee.

Harris’s net worth is as much as $6.3 million, based on the assets listed in her latest Senate financial disclosure, filed in May. That makes her wealthier by some measures than even her presidential running mate: Biden’s assets, according to his 2018 tax return, amounted to as much as $2.7 million.

By comparison, Sen. Elizabeth Warren—who initially ran alongside Harris and Biden for the Democratic presidential nomination, and was once thought to be a front-runner for Biden’s VP pick—disclosed up to $8.9 million in assets in her latest Senate financial filing. The financial disclosures include bank and investment accounts but not other assets such as real estate and property holdings.

Of Harris’s wealth, much of the money is held in the name of her husband, Douglas Emhoff, a partner at the big international law firm DLA Piper. Excluding Emhoff’s assets, Harris still has up to $1.7 million in her accounts.

As for income, Harris was also one of the highest-earning of the Democratic candidates, second only to Biden himself, according to a New York Times analysis last year. (The analysis predated Michael Bloomberg’s entry into the presidential race.) Harris and her husband reported nearly $1.9 million in adjusted gross income in 2018, the candidate’s most recently released tax returns show. They paid an effective 37% tax rate on that income—the highest rate of all the Democratic presidential candidates, including Biden, even though his income was greater.

Biden’s tax returns show he reported almost $4.6 million in income in 2018, paying an effective rate of 33.8%.

More recently, Harris disclosed that she personally made $277,763 in income in 2019 in her latest Senate financial disclosure, all from book publishing advances.

Politically, Harris has proposed some changes to U.S. tax policy, including taxing stock trades at 0.2% and bond trades at 0.1%—a change that could potentially increase the taxes she pays on her own investment accounts, which include both stock and bond funds.