President Barack Obama cranked up campaigning on his road to the Democratic National Convention in the swing state of Colorado on Sunday, as top aides slammed his Republican opponent. With the election barely nine weeks away, Obama is locked in a tight contest against Mitt Romney, whose campaign has doggedly stood its ground and even upstaged the slick fundraising that swept the incumbent to power in 2008. The current campaign has been a grinding battle so far for the president: the euphoria of four years ago is a fading memory and Obama will use the Democratic National Convention, starting Tuesday, to seek a fresh mandate. Obama's current tour of battleground states, dubbed the "Road to Charlotte," in reference to the city in North Carolina where the convention takes place, has underlined the closeness of the race. His bid for a second White House term hinges on a handful of swing states but the convention is a four-day opportunity for Democrats to dominate the political conversation despite the backdrop of a bumpy US economic recovery.
