MEXICO CITY (Reuters) -Mexican President Andres Manuel Lopez Obrador's verbal attacks on a charismatic opposition rival have raised her profile and fed concern among some supporters that far from derailing her campaign for the presidency, he is undermining his own party. Since Senator Xochitl Galvez announced on June 27 that she was running for the top job, the leftist Lopez Obrador has mentioned her by name more than 50 times during his daily press conferences - and public support for her is gr