WASHINGTON - The U.S. Congress faces a tight deadline to avoid a government shutdown as lawmakers begin returning to Washington next week, complicated by bitter conflicts between Republicans and Democrats over the next package of coronavirus aid. The Republican-led Senate is due back on Tuesday, while the Democratic-led House of Representatives plans to hold votes on bills starting the following week. With congressional elections on Nov. 3, both chambers have very few days left to finish work as lawmakers plan to campaign in their home states for much of October. The federal fiscal year ends on Sept. 30, so they will have to scurry to reach a deal on legislation funding government programs and averting a partial shutdown that could be especially damaging to lawmakers facing re-election in November. On Thursday, White House Press Secretary Kayleigh McEnany expressed optimism that agreement will be reached in a timely way. Congress is widely expected to pass a temporary measure mainly f