Democrats' House Flip Odds Decline After Southern States Redraw Maps

Democrats' chances of securing a majority in the House of Representatives have decreased in prediction markets after several Republican-led states in the South redrew their congressional maps ahead of the 2026 midterm elections. Historically, the party holding the White House has lost seats during midterm elections.

This pattern had contributed to Democratic optimism about regaining control of the House in November. The Supreme Court decision in Callais v. Louisiana, which eliminated a second majority-Black district in that state, has allowed other states to adjust their maps.

Alabama, Florida, Louisiana, Tennessee and Virginia have redrawn districts in ways that could enable Republicans to gain seats through redistricting. Prediction markets continue to show Democrats as favorites to take control of the House. Their probabilities have declined, however, after the redistricting actions.

That figure had been 86 percent one month earlier on April 13. Polymarket showed an 80 percent chance for Democrats on Wednesday. The platform had listed an 87 percent probability at the beginning of April. These adjustments reflect the potential for map changes to alter the number of competitive districts in the affected states.

The redistricting process remains subject to further legal and procedural steps before the 2026 elections.