U.S. President Joe Biden heads into a crucial debate with rival Donald Trump this week armed with new immigration and border policies that his backers hope will boost his standing among skeptical voters. Biden announced two major policy moves in June that seek to address migration challenges and woo the electorate: an asylum ban to cut illegal crossings at the U.S.-Mexico border and a sweeping legalization for long-term residents married to U.S. citizens. The two policies - one aimed at...