(CNN) Democrat Gil Cisneros on Thursday took the lead over Republican Young Kim in the race to replace retiring Rep. Ed Royce in California's 39th Congressional District, according to the latest vote reports.

Cisneros has taken the lead with 50.2% of the vote, just ahead of Kim's 49.8%. The two are separated by fewer than a thousand votes.

Should Cisneros' lead hold up, it will be yet another Democratic win in the week and a half since Election Day and would further increase the Democratic gains in the House of Representatives. The party won control of the chamber from Republicans for the first time since losing it in the 2010 midterm elections.

Kim, who had led the race since election night, would be the first Korean-American woman sent to the House, if elected. A former staffer for Royce, Kim has emphasized her immigrant experience throughout the race.

But the district is more than a third Latino and encompasses parts of Orange and Los Angeles counties. The racially diverse areas of those counties and high Latino turnout could push the district to Cisneros, a former Navy officer.

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