The Democrats took back the House with a surge of fresh new candidates and an outpouring of voter enthusiasm Tuesday, breaking the GOP’s monopoly on power in Washington and setting the stage for a multitude of investigations of President Donald Trump that could engulf his administration over the next two years. Ending eight years of Republican control that began with the tea party revolt of 2010, Democrats picked off more than two dozen GOP-held districts in suburbs across the nation on the way to securing the 218 seats needed for a majority. As of early Wednesday, Democrats had won 219 races and the Republicans 193, with winners undetermined in 23 races. Democrats lead in nine of those, Republicans in 14. The final count is likely to leave Democrats with a narrow majority that could be difficult to manage and preserve. Democratic Leader Nancy Pelosi, who is seeking to reclaim the gavel as House speaker, called it a “new day in America.” She saluted “those dynamic, diverse and incredible candidates who have taken back the House for the American people.” With the Republicans keeping control of the Senate, the outcome in the House could mean gridlock for Trump’s agenda on Capitol Hill ” or, conversely, it could open a new ...