By Lynn La, CalMatters

California voters passed Proposition 50 on Tuesday, clearing the way for the state to redraw its congressional districts in a manner that could enable Democrats to regain the U.S. House of Representatives in next year’s midterm elections.

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Though the U.S. Department of Justice sent election monitors to five California counties — prompting state and some local leaders to deploy their own election monitors — voting across the state went smoothly for the most part. Because of the atypical high voter interest in this year’s special election, some voting centers and college campuses reported long lines. By Election Day, over 7.2 million votes were already submitted.

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The gerrymandering measure was a high-stakes gamble for Gov. Gavin Newsom, who initially floated the idea in the summer as a counter to Texas Republicans’ own mid-cycle redistricting efforts. Prop. 50 proponents poured more than $120 million into Newsom’s committee supporting the measure, while opponents raised $44 million. Groups unaffiliated with any Prop. 50 campaign spent at least an additional $26 million to influence voters.

With Prop. 50’s passage, five GOP congressmembers now face steep odds to re-election, write CalMatters’ Jeanne Kuang and Maya C. Miller. U.S. Rep. Kevin Kiley’s 3rd District, for example, currently encompasses the Sacramento suburbs, but it will change to pull in Democratic voters from the city. The Rocklin Republican opposed Prop. 50, and pledged to run for re-election in the redrawn district.

Meanwhile, Trump has described Prop. 50 as unconstitutional and a “giant scam.” Despite unproven claims of widespread voter fraud, the president remains a vocal critic of mail-in voting, and vowed to give California’s mail-in ballot results a “very serious legal and criminal review.” The Justice Department plans to monitor election proceedings in California until Thursday.