BOSTON -- Millions of dollars and thousands of man hours have been spent and now it's all up to Massachusetts voters to decide who they want to run in their respective parties as the state moves to replace Sen. Edward M. Kennedy in Washington.

Kennedy died in August after serving the commonwealth in the U.S. Senate for nearly 40 years and in Tuesday's primary election voters will narrow the field of competitors to two.

Polls opened at 7 a.m. Tuesday and are scheduled to stay open until 8 p.m. Candidates from both the Democratic and Republican parties showed up at their hometown polling places first thing in the morning to cast their votes.

Democrat and City Year founder Alan Khazei went to his Brookline precinct with his wife and two young daughters to vote and then worked the crowd outside. He said he hoped there was a surprise turnout for the race.

Democrat Stephen Pagliuca thanked his supporters after voting near his Weston home. After spending more than any other candidate to build visibility in the race, the Celtics owner said he felt confident he had a good shot at winning.

U.S. Rep. Michael Capuano voted in Somerville. With mild public interest in the race and a moderate turnout of anywhere from 10 percent to 25 percent predicted, he said it will all come down to which candidate is most successful in getting voters to go to the polls.

"It's very simple. Picking up the phone, talking to people like you and saying, 'Who you going to vote for?' If you're going to vote for me and if you are we're going to call you again and again and again. If not, we encourage you to go to Aruba," he said, joking.

Democratic front-runner Martha Coakley voted in Medford and said she's done all she can do.

"It's really in the hands of the voters now, so, we're going to watch closely now but I think we've done everything we could," she said.

Republican candidate Jack E. Robinson worked the commuter crowd outside of South Station, using a bagpipe player to draw attention, and Republican state Sen. Scott Brown voted in Wrentham, then said he was off to do more work.

"I'm going to actually get on the phones," he said.

NewsCenter 5 will have live election results Tuesday and will broadcast a one-hour election special starting at 10 p.m.