Odinga told the stadium crowd that Kenya has stagnated the last 50 years because the status quo has remained in power. "This can only change by voting in the forces of change," Odinga said.
He also appeared to attack Kenyatta, saying that the son of a snake is a snake. "It's time we end dictatorship, impunity and land grabbing," he said. Kenyatta is the son of Kenya's first president.
Monday's vote is the most important and complicated in the country's 50-year history. Despite efforts to promote peace, there are many reasons why the vote could turn tumultuous.
The Somalia militant group al-Shabab may try to attack voters or disrupt the vote; a secessionist group on Kenya's coast has threatened violence; new political divisions known as counties will see 47 new races for governor, creating sources of new friction; and tensions are high in some regions between Odinga's tribe — the Luo — and Kenyatta's tribe — the Kikuyu.
Odinga or Kenyatta must win at least 50 percent of the vote in order to win the election Monday. There are eight presidential candidates, so it's likely the two will face each other in a run-off in April, a situation that analysts believe will raise tensions because of the increased focus on the two men.
Associated Press reporter Jason Straziuso contributed to this report.
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