The November midterm elections could transfer control of one or both chambers of Congress to Democrats, but a new majority would not automatically end President Donald Trump’s military campaign against Iran. Trump would remain commander in chief and could veto legislation, leaving lawmakers to rely on war-powers resolutions, funding decisions and other forms of pressure.
The conflict began on Feb. 28, 2026, without a congressional declaration of war or a specific authorization for military force. Under the War Powers Resolution, presidents generally must obtain congressional approval or withdraw forces after 60 days. The administration has argued that a ceasefire interrupted that clock and has also challenged the law’s constitutionality.
Congress has repeatedly tried to restrict the operation. The House passed a withdrawal measure by 215-208 in June, with four Republicans joining Democrats. A subsequent Senate vote failed 49-50, even as four Republicans backed ending the war.
Those votes were largely political statements and did not require Trump’s signature. Congress could exert greater leverage by withholding military funds, but Republicans have so far resisted that approach.
The conflict has become a major electoral liability for Republicans. About two-thirds of voters identify the war as a top election issue, while roughly half prefer Democratic control of each chamber. Even if Democrats win, however, they would need sustained bipartisan support to overcome presidential vetoes or impose binding limits, keeping Trump’s authority over military decisions largely intact.