Republicans face a serious challenge to their 53-47 Senate majority in the November midterm election, with five of the six Senate seats rated toss-ups by Cook Political Report held by the GOP. Only one of those six seats is in a state President Donald Trump lost in 2024. Trump’s approval rating stands at 38% in Nate Silver’s Silver Bulletin polling average, as surveys in recent months have shown record-low approval amid growing fatigue with the Iran war and its effect on the economy. The president’s party typically struggles in midterms, when lower turnout and opposition voters’ desire to register their view of the administration can work against the party in power. Republicans also hold a narrow 218-213 House majority, but most polls give Democrats an advantage on the generic congressional ballot, which measures voter preference for Congress without naming individual candidates. A Democratic takeover of either chamber, or a split Congress, could constrain Trump’s agenda. Democrats are preparing investigations if they regain control of one or both chambers, including probes into whether Trump used the presidency for personal enrichment.