Straw poll voting began October 29, and continued until 7 p.m. Saturday. More than 3,600 people voted in person or online.
"On the in-person voting, Governor Romney got 35 percent of the vote. He was the victor of in person voting. But Herman Cain got 29 percent showing that he is still very much a contender in this race," said U.S. Sen. Mark Kirk.
At a voting place in Libertyville on Saturday, voters were joined by Kirk and State Republican Party Chairman Pat Brady. Voters had to pay a $5 fee to cover the cost of the poll.
Kirk said he hopes this starts a tradition. He wants candidates to come to Illinois to seek votes and not just to raise money.
The Illinois primary is March 20. Illinois is considered a state with much Democratic support. The state's electoral votes in 2008 went to President Barack Obama, who is a former U.S. senator and state senator from Illinois.
Herman Cain won a tea party straw poll last month in suburban Chicago, receiving 77 percent of votes from TeaCon 2011 participants. The convention included representatives from tea party groups in Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri and Wisconsin.
The Associated Press contributed to this report.