With the last campaigns only one day in the rearview mirror, Bolivia’s political world has delved into preparations for an unprecedented runoff election that will reveal the extent of a centrist senator’s unexpected traction in the presidential vote.

Early results in Bolivia's presidential election show the country headed for an unprecedented runoff following a vote in which a dark horse centrist, Sen. Rodrigo Paz, drew more votes than the right-wing front-runners, although not enough to secure an outright victory.

Bolivians have headed to the polls for a pivotal election that could end the long reign of the leftist Movement Toward Socialism party.

Street clashes have erupted in Bolivia's capital of La Paz as hundreds of supporters of ex-President Evo Morales marched toward the country's top electoral court to push for their leader’s candidacy in presidential elections later this year.