Republicans secured control of the House by protecting vulnerable incumbents and defeating Democrats in competitive districts, giving President-elect Donald J. Trump a unified Congress to advance his agenda. The margin of the Republican majority in the House remained uncertain as votes were still being counted in critical contests. Despite the resignation of Representative Matt Gaetz and a slim majority, Republicans plan to push forward with legislation including tax cuts and border security measures. Democrats faced losses in key battlegrounds like Pennsylvania, while some incumbents outperformed expectations, ultimately falling short of regaining control of the House.