President Barack Obama on Thursday tapped four big Democratic Party donors for plum ambassadorships in Europe and Latin America while naming six career diplomats to posts in Africa, the Mideast and the Pacific. Washington lawyer Howard Gutman, who raised more than $500,000 for Obama's campaign and personally contributed the maximum $4,600 to it, was nominated to be the next U.S. envoy to Belgium, the White House said in a statement. Gutman also contributed $2,300 to now Secretary of State Hillary Rodham Clinton's presidential campaign, according to the Center for Responsive Politics, a nonpartisan group that tracks money in politics. Obama...