No violence was reported Tuesday as Liberians took to the polls in a runoff presidential election, though one analyst said the incumbent could emerge tarnished. Despite a call for a boycott by opposition leader and presidential election runner-up Winston Tubman, Liberians headed to vote Tuesday following reports of conflict between police and Tubman backers the previous day. \"We\'re hoping that yesterday\'s incident and the unfortunate violence … is just an isolated incident,\" U.N. spokeswoman Yasmina Bouziane was quoted by The Wall Street Journal as saying. \"As of now, we don\'t see any major flash points.\" Tubman accused Liberia\'s election committee of supporting incumbent President Ellen Johnson Sirleaf, co-winner of this year\'s Nobel Peace Prize. Lydie Boka, an analyst at French risk consultant group Strategico, told the Journal that support from former warlord and third-place candidate Prince Johnson could tarnish Sirleaf\'s reputation, whose Nobel prize holds little clout at home. \"It\'s embarrassing for her -- for her Nobel prize,\" said Boka. \"She\'s really in a bad spot at the moment.\" Before the Nobel Peace Prize announcement last month, Liberia\'s Truth and Reconciliation Commission recommended a ban on public office for Sirleaf because of her support for former Liberian President Charles Taylor, accused of being responsible for atrocities by rebels in Sierra Leone during the country\'s decade-long civil war. She has since backed away from Taylor.