(For a Reuters live blog on U.S., UK and European stock markets, click LIVE/ or type LIVE/ in a news window.) * Gilead up as remdesivir wins approval for treating COVID in U.S. * Intel slumps as quarterly margins fall * American Express drops as profit falls short of estimates * Indexes dip: Dow 0.53%, S&P 0.18%, Nasdaq 0.30% (Updates to early afternoon) Oct 23 (Reuters) - Wall Street’s main indexes fell in Friday afternoon trading as investors fretted over an impasse in Washington on the new coronavirus aid bill, while turning cautious ahead of the Nov. 3 presidential election. The biggest weight on the three indexes was a 10.5% slump in chipmaker Intel Corp after it reported a drop in margins as consumers bought cheaper laptops and pandemic-stricken businesses and governments clamped down on data center spending. Uncertainty over the timeline of the relief legislature has been weighing on Wall Street’s major indexes, which were set to cap a choppy week lower. U.S. House Speaker Nancy Pelosi said it still was possible to get another round of COVID-19 aid before the election, but that it was up to President Donald Trump to act, including talking to reluctant Senate Republicans, if he wants it. Treasury Secretary Steven Mnuchin on the other hand said a deal was possible if Pelosi was willing to compromise. “We are kind of on a hold at this point ... still waiting for something to come out of Washington,” said Paul Nolte, portfolio manager at Kingsview Asset Management in Chicago. “Our base case is that we don’t get a meaningful stimulus package until after the election and probably not until first quarter.” Meanwhile, a record 50 million Americans cast ballots, eclipsing total early voting from the 2016 election. President Donald Trump and Democratic rival Joe Biden debated on Thursday for the last time to persuade the few remaining undecided voters 11 days before their contest. Heading into the debate, Trump trailed former vice president Biden in national polls, but the contest is much tighter in some battleground states where the election will likely be decided. At 12:41 p.m. ET, the Dow Jones Industrial Average was down 148.98 points, or 0.53%, at 28,214.68, the S&P 500 was down 6.23 points, or 0.18%, at 3,447.26. The Nasdaq Composite was down 34.27 points, or 0.30%, at 11,471.74. The energy index dropped 1%, the most among 11 major S&P sectors. The third-quarter earnings season chugged along, with about 84% of the 135 S&P 500 companies that have reported so far topping quarterly profit estimates, according to Refinitiv data. Next week’s focus will be on results from Big Tech companies Apple Inc, Facebook Inc, Amazon.com Inc and Google-parent Alphabet. Gilead Sciences Inc rose 0.9% as its antiviral drug remdesivir became the first and only drug approved for treating patients hospitalized with COVID-19 in the United States. American Express Co dropped 3.7% as it missed estimates for third-quarter profit after its customers spent less during the COVID-19 fueled economic slowdown and it set aside money for potential payment defaults. Advancing issues outnumbered decliners by a 1.08-to-1 ratio on the NYSE. Declining issues outnumbered advancers for a 1.07-to-1 ratio on the Nasdaq. The S&P index recorded 25 new 52-week highs and no new low, while the Nasdaq recorded 50 new highs and 12 new lows. (Reporting by Medha Singh and Shivani Kumaresan in Bengaluru; Editing by Anil D’Silva and Maju Samuel)