WASHINGTON — MAGA Inc., a super PAC aligned with President Donald Trump, is preparing a late-stage reshuffling of its midterm spending, pulling back from some House races and directing more attention to Senate contests it considers essential to retaining the Republican majority. The group has several hundred million dollars remaining, according to three Republican officials familiar with its strategy. In the final three weeks before the November election, it plans to make major spending decisions alongside other leading GOP super PACs, the officials said. They spoke anonymously to discuss the strategy. Ohio, Alaska and Iowa have become central to the group’s Senate plans, the officials said. MAGA Inc. is weighing where to deploy its resources as Republicans seek to hold their majority in the chamber. In the House, MAGA Inc. and a leading Republican super PAC plan to stop spending in Michigan’s 8th Congressional District by the middle of this week, according to one of the officials. The decision signals that Republican strategists see Democratic Rep. Kristen McDonald Rivet as holding an advantage over GOP challenger Tom Smith. The groups are considering similar pullbacks in other House races that have grown less favorable to Republicans. The planned cuts would narrow the map for Republican outside spending, shifting money away from races viewed as harder to win and toward contests the groups believe could determine control of the Senate. The strategy also underscores how large outside political organizations can shape the final weeks of campaigns by directing substantial sums toward selected races.