House Republican leaders warned rank-and-file members Wednesday that they need to make sure their coffers are full so they can take on Democratic challengers as early as possible this year, now that a Democrat is threatening to win a “wake-up call” election held in Pennsylvania on Tuesday.

The warning, delivered by the House GOP’s campaign chief and Republican leaders at election headquarters, came after Tuesday night’s apparent victory by Conor Lamb in Pennsylvania’s 18th Congressional District, which President Trump won by 20 points in 2016. That result weighed heavily over the GOP meeting Wednesday morning.