President Barack Obama has a 60% chance of winning the election in November if share prices rebound, says Trevor Greetham, asset allocation director at fund management firm Fidelity. Greetham notes that a dip in the economy between now and the election could have the opposite effect and prove beneficial for Mitt Romney. "Historically, stock markets do tend to rise in an election year and, while this has often been the case in the past, it is important to bear in mind exogenous factors which may affect markets," said David Blake of Jupiter Asset Management. The debt crisis in Europe is one such factor.