Nov 2 (Reuters) - Wall Street’s main indexes bounced back on Monday from their steepest weekly loss since March as investors geared up for an event-packed week centered around the U.S. presidential election. The Dow Jones Industrial Average rose 189.68 points, or 0.72%, at the open to 26,691.28. The S&P 500 opened higher by 26.24 points, or 0.80%, at 3,296.20, while the Nasdaq Composite gained 98.86 points, or 0.91%, to 11,010.45 at the opening bell. (Reporting by Medha Singh in Bengaluru; Editing by Anil D’Silva)