U.S. stocks rose today, sending the S&P 500 up from yesterday’s three-week low, as investors predicted that the government shutdown will have only a limited impact on the economy. ???We have gone through this before, it???s not too surprising that investors aren???t frightened by it,???Bruce Bittles, chief investment strategist at RW Baird & Co., said. ???The selling pressure lifted, and that has encouraged a lot of buyers here looking into buying the dip.???