(S (S (NP (BASENP (NNP Andres) (NNP Manuel) (NNP Lopez) (NNP Obrador)) (PP (IN of) (NP (BASENP (DT the) (JJ left-wing) (NNP Democratic) (NNP Revolution) (NNP Party)) (PRN (LRB -LRB-) (BASENP (NNP PRD)) (RRB -RRB-))))) (COMMA ,) (VP (VP (VBZ continues) (S (VP (TO to) (VP (VB insist) (SBAR (IN that) (S (BASENP (DT the) (NN election)) (VP (VBD was) (VP (VBN rigged))))))))) (CC and) (VP (VBZ has) (VP (VBN vowed) (S (VP (TO to) (VP (VB continue) (S (VP (VBG fighting) (BASENP (DT the) (NN result))))))))))) (PERIOD .))