The Cook Political Report has moved 15 House race ratings toward Democrats and now projects a Democratic pickup of five to 15 seats in November's midterms, which would put the party at 220 to 230 seats in 2027.

Democrats now hold 215 seats and need just three more to win back the chamber, according to Cook's September 25 update. The forecaster says most competitive races sit in districts President Donald Trump won, where he is 'deeply underwater' on the economy.

Separately, Reuters reported that Republicans are pouring money into at least 39 House races once considered safe, after internal polling showed they could be vulnerable. Republican strategist Ron Bonjean said the party is 'playing defense in some of the strongholds that they're used to not having to worry about.'

Republicans hold a 218-214 majority, with one independent caucusing with them and two vacancies. Democrats would need a net gain of four seats to take control.

With six weeks to the November 3 vote, spending shows both sides bracing for a fight over the narrowest of House majorities.