they could establish their own civil rights commissions. In 1947, he was reelected with 102,000 votes over his opponent's 52,000 votes. As a delegate to the 1948 Democratic National Convention, he led the call for a strong civil rights plank. In his address, he said, "There are those who say to you – we are rushing this issue of civil rights. I say we are 172 years late. There are those who say – this issue of civil rights is an infringement on states rights. The time has arrived for the Democratic Party to get out of the shadow of state's rights and walk forthrightly into the bright sunshine of human rights." Humphrey was elected to the United States Senate in the 1948 election and served many years as a prominent Minnesota politician, including Vice President of the U.S. from 1965 to 1969. W. Harry Davis, who later served 20 years on the Minneapolis School Board, agreed to run for mayor in 1971, becoming the city's first black mayoral candidate supported by a major political party. White supremacists were still present in Minneapolis, and threatened his family daily during the campaign. The police department guarded their home and the FBI gave them protection dogs. Davis also received support from white politicians including Humphrey, Donald M. Fraser, and Walter Mondale. Twenty years later, Minneapolis elected its first African American mayor, Sharon Sayles Belton. To date, she has been the city's only non-white mayor. In 1968, Dennis Banks and Clyde Bellecourt were among those who founded the American Indian Movement to advance civil rights for Native Americans. A growing city From about 200,000 in the 1900 Census, Minneapolis soared to its highest population recorded in 1950 of over 521,000 people. The main growth of the city was in part due to an organized private streetcar system. With 140 million passengers by 1920, the streetcars ran down important roads extending from Downtown Minneapolis. Neighborhood residential development out of the core mostly dates around the turn of the century as a result of this system. This growth also allowed Minneapolis to annex land from neighboring villages and townships which subsequently pushed the incorporation of today's inner ring suburbs. The streetcar system was built by Twin City Rapid Transit and operated efficiently through 1949, with a program of reinvesting their profits into system improvements. However, in 1949, New York investor Charles Green gained control of