The U.S. Capitol is seen on the second day of the federal government shutdown on October 2, 2025, in Washington D.C.With the government shutdown nearing its one-week mark, investors may be monitoring how the stalemate in Washington is affecting their portfolios.So far, stocks have been doing just fine. Although the S&P 500 was down slightly on Tuesday, the index returned 0.80% between Oct. 1 and Oct. 6 — and even notched several new highs.And it turns out that market gains during and following a government ...