The Senate decided to delay its vote on its Obamacare repeal-and-replace bill as Senate Majority Leader Mitch McConnell faced lack of support even within his own party. The delay provoked a selloff in healthcare, pulling the Nasdaq further into the red. Western Digital Corp. (WDC) - Get Report was caught up in the larger tech selloff even after bumping its fourth-quarter profit guidance higher. The revision is based on higher gross profit estimates driven by sales of flash memory chips. A milestone for Facebook Inc. (FB) - Get Report : CEO Mark Zuckerberg announced that the social network has reached two billion monthly users for the first time. Shares were lower alongside the other FANG stocks. J.C. Penney Co. (JCP) - Get Report rose after Gordon Haskett Research Advisors upgraded its rating on the stock to hold from reduce. Analysts are optimistic the retailer can reach its fiscal 2017 same-store sales forecast.