In February, the Pennsylvania Supreme Court set up an epic clash when its new map paired two incumbents in the Pittsburgh suburbs in the new 17th CD. But a Monmouth University poll shows newly elected Democratic Rep. Conor Lamb leading three-term GOP Rep. Keith Rothfus 51 percent to 39 percent. It corroborates data parties have seen privately, and we're moving our rating from Toss Up to Lean Democratic.

The new 17th CD is close to Lamb's dream district. It unites almost all of suburban Allegheny County, including his home and political base of Mt. Lebanon, with Beaver County, which has a strong blue-collar Democratic heritage.

On the whole, it's much less Republican and more Pittsburgh-centric than either incumbent's current seat. Both Lamb and Rothfus's current seats voted for President Trump by around 20 points. But the new 17th CD voted for Trump by just two points, 49 percent to 47 percent (its PVI is R+3, versus R+11 in both the current 12th and 18th CDs). It also sports a double-digit Democratic voter registration advantage.

Technically, Lamb currently represents just

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