Democrat Conor Lamb, the apparent victor in last week's Pittsburgh-area House special election, filed Tuesday to run again this November in a newly drawn district that could be home to one of the marquee match-ups of the 2018 election cycle.

Lamb ran in Pennsylvania's 18th Congressional District special election under old boundaries that have since been ruled unconstitutional. His November bid will be within the new map, drawn by the state Supreme Court.

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The Democrat will run in the new 17th District, where he hopes to face Republican Rep. Keith Rothfus Keith James RothfusCNN's Tapper tried to talk GOP candidate out of running against Democratic incumbent: report Lobbying world Conor Lamb gets 2020 challenger touted by Trump MORE in the general election. Rothfus had once been expected to cruise to reelection in his heavily Republican district, but the new lines should make the seat far more competitive.

While Lamb spent the past few months promising voters that he'd run for a full term in November, he didn't confirm where he'd file. Candidates had until Tuesday afternoon to turn in a petition with 1,000 signatures to be eligible for the ballot.

Lamb will be the favorite in the Democratic primary, but he will have to defeat at least a couple challengers in order to make it to the match-up with Rothfus. Two other candidates have filed petitions to run in the 17th District's Democratic primary on May 15, and more could file before the end of the day.