Key TakeawaysFinancial service companies, along with the industrial and energy sectors and Tesla, led the S&P 500's rally Wednesday.Companies that issue credit cards performed particularly well, including Discover Financial Services and Synchrony Financial.Other gainers include cruise operators, commercial transit businesses and energy companies. The S&P 500 rose Wednesday, lifted by the strength of credit-card issuers, Tesla (TSLA) and the industrial and energy sectors in the first trading session after El ...