Reprinted with permission from Called to Colombia:
Santos was the strong front runner early in the campaign. Colombia held congressional elections in March, and the conservative parties did very well, taking a majority of seats. (The Congressional elections have also had significant levels of fraud.)
In April, Fajardo joined Mockus on the Green ticket, and polls began to show a signifacnt surge. Starting from around 10%, Mockus jumped into the 20's for a few weeks, and then in May into the 30's. In April, Mockus announcened that he is in the early stages of Parkinson's Disease, which traditionally would have been a large liability for a politician. Surprisingly, Mockus's poll numbers continued to rise, even jumped on the news. We attribute this and much of Mockus' popularity to the Colombian people's thirst for a more transparent, honest class of political leadership.
Santos numbers have dropped, and the most recent polls have shown Mockus and Santos close to a dead heat, around 35%. The other candidates are all now under 10%. The campaign has been mostly focused on Mockus' rise.
In general, President Alvaro Uribe factors heavily in this campaign. The candidates are often portrayed by how close they are to Uribe's policies. Very roughly, on the generally pro-Uribe side, Santos is seen as the closest, then Lleras, then Sanin as the more moderate pro-Uribe candidate. On the other side, Pardo is seen as more moderate, yet critical of many Uribe actions, then Mockus, and Petro as the most critical of most Uribe policies.
The other significant factors are Colombia's neighborly (or not so much neighborly) relations. Most significant has been the candidates' stance on the idea of carrying out attacks against the FARC on foreign soil. This occurred in 2008 under Uribe and Santos, and has proven a very large stumbling block between the two countries. In debates, Santos vowed to continued these types of attacks, which led Ecuador to begin processing criminal charges against him for the earlier attacks. Other candidates have shown varying degrees of opposition to foreign attacks, with Mockus and Petro, showing the most emphasis on peaceful relationships.
A good site for English language news concerning the election is Colombia Reports 2010 Election site.