Associated Press: European leaders pressed Congress and the White House on Tuesday to unite on a plan to combat global warming, even as a Republican boycott forced a delay of votes in a key Senate committee, demonstrating the deep partisan rift. An emotional plea for action by German Chancellor Angela Merkel in an address before Congress was met with silence from most Republicans, while Democrats stood and applauded. The Europeans as well as the U.S. were pressured in turn by African nations to …