A majority of Americans believe the United States should improve its long-strained relationship with Cuba and reestablish diplomatic and business ties, Reuters quoted an opinion poll as showing today. A Cuba Business Bureau/Insider Advantage poll of 401 people showed that 58 percent of those surveyed supported full diplomatic relations with Cuba, while 33 percent opposed it. The poll, which had a margin of error of plus or minus five percentage points, also showed that 61 percent believed U.S. citizens should be allowed to travel to Cuba and 57 percent thought Washington should allow U.S. companies to do business in Cuba. The United States has lifted some limits on Cuban Americans traveling and sending money to Cuba and initiated talks with Havana on migration and mail service. But U.S. President Barack Obama has said the economic embargo will stay until Cuba improves human rights and frees political detainees.