Democrat Derek Tran has defeated two-term Republican U.S. Rep. Michelle Steel in a Southern California House district that was specifically drawn to give Asian Americans a stronger voice on Capitol Hill.

In a major victory for Democrats, first-time candidate Derek Tran defeated Republican Rep. Michelle Steel in a hotly contested Orange County congressional race that became one of the most expensive in the country.

New vote tallies from Orange and L.A. counties late Tuesday afternoon showed Tran expanding his lead to 613 votes over incumbent Steel.