In the race to fill the vacancy left by state Sen. Pam Resor's (D-Acton) retirement, two well-credentialed candidates have quickly organized campaigns in what some are saying is going to be one of the most competitive races this cycle.

State Rep. Jamie Eldridge (Acton) is carrying the standard for the Democrats in the race, after an unsuccessful run for Congress in the 2007 special election for the 5th district seat (he came in third in that race's Democratic primary). Eldridge has represented part of the Middlesex and Worcester Senate district in the House since 2002.

Asked why he is running for the Senate, Eldridge said he views it as the next step in fighting for the concerns of his constituents.

"I'm proud of the successes I've had as a state representative in securing investments for the communities I represent now," Eldridge told PolitickerMA.com. In particular, he said, he is proud of his work to increase education aid, pass universal healthcare legislation and increase local aide to improve public safety.

"This," he said, "is an opportunity to help more people and have a bigger role in passing important legislation."

Eldridge said he has strong ties to the district, having worked on former state Sen. Bob Durand's campaign in 1990 and managing Resor's reelection campaign in 2000.

The sagging economy is the top priority in the district, Eldridge said. "What I've experienced going door to door," he said, "the biggest issue on voters' minds is jobs and the economy...Voters want to know what the state is doing to expand economic opportunity."

If elected, Eldridge said he hopes to address those concerns by working to pass legislation that brings business and jobs to the district. He cites his work to help bring Bristol Myers Squibb to Fort Devens as an example of his dedication to economic issues.

But Republicans in the Senate district say Eldridge's progressive politics are out of line with the majority of the district's voters. The district supported Republican governors, said David Stone, the chair of the Acton Town Republican Committee, until current Gov. Deval Patrick (D-Milton) carried it in 2006.

"The district has a pretty wide middle that is more conservative than Jamie Eldridge," Stone said. "Jamie is as liberal as they come in the state legislature."

Eldridge disagreed with that charge and said he believes his positions are right in line with those of the voters in the district. "What I have heard in going door to door and from my constituents," he said, "is their concerns are my priorities. Investing to create jobs, increasing state education aid and local aid to improve public safety, investing in the commuter rail and protecting the environment -those are priorities that I've stood for."

Democrats in the district agreed. "I believe that people in our district highly value Jamie Eldridge's progressive stand on issues like the environment, education funding, and social issues," said Dennis Bradley, the chair of the Harvard Democratic Town Committee. "Moreover, I think that his constituents in Harvard appreciate how clearly he articulates his position on these issues and greatly respect his hard work in pursuing them."

Nevertheless, if the middle Stone mentioned does exist, Republican contender Steven Levy is hoping to take advantage of it. Levy is currently serving his second term on the Marlborough City Council where he chairs both the Human Services and the Legislative and Legal Affairs committees. He is also the owner of Ledger Plus, a local accounting company, and the chief financial officer of a local nonprofit that helps people suffering from addictions.

Levy said he is running because the legislature has mismanaged the state's finances. "I never anticipated that I'd be running for the state legislature," he said, "but as I watched what was going on in the state I became more frustrated in the lack of control in spending and taxation. The legislature has failed to maintain any sort of fiscal responsibility."

"I just got the sense that the legislature has lost touch," Levy said. "Any person with common sense just shakes their head."

Like Eldridge, Levy said the economy was the top concern of voters in the district. The rising price of gas, he said, is also on voters' minds.

"We have limited ability to address the price of gas locally," he said, "but the one thing we can do is to pursue alternate sources of energy."

Levy said the legislature needs to focus on creating energy efficient jobs with carefully selected investments. "If we are going to make investments in Massachusetts," he said, "let's invest in alternative energy sources."

Republicans in the district are excited about Levy's campaign, Stone said. "Steve is in a very good position being a successful city councilor in the district," he added.

Despite hailing from Marlborough, the largest city in the district, Levy faces several challenges. Eldridge is more well-known throughout the district and Levy has to work to raise his profile outside of Marlborough. And even though the race is for an open seat, Eldridge has pseudo incumbency status since he has been representing part of the district in the state House of Representatives.

"The danger with a guy like Eldridge," Stone said, "is he won a race for an open seat and the Democrats are pretty well organized in the district he won. So the conventional wisdom is that he'll win."

Levy has received that message loud and clear and has started canvassing the district to raise his name recognition. He has hired a fulltime campaign manager and has set a goal of knocking on 20,000 doors before the election. So far, he said, he's already closing in on 4,000.

"Best way to campaign," he said, "is to go out and talk to people face to face."

Eldridge said he is similarly dedicated to a grassroots campaign. He has hired a fulltime field director and campaign manager and plans to focus his campaign on going door to door in the district. He also plans to do some mailings later in the campaign as well as hold some events where voters can meet him.

"I've always been very committed to grassroots," he said. "In 2006 I was the Senate district co-coordinator for Deval Patrick's campaign for governor. I'm using the same approach in this race."