At Third Way, a new advocacy group for centrist Democrats, a simple line graph in the group’s conference room bears a stark reminder of how far Democratic fortunes have fallen in the last half-century.

The graph shows the number of Democratic Senators steadily declining, from 75 in 1939 to 44 today. Nearby, a county-by-county map of 2004 presidential election results shows splotches of blue drowning in a sea of red support for President Bush.

Third Way, which rolled out in the wake of the election, has its work cut out for it.

Even as the group struggles to reverse electoral tides, it must also distinguish itself within the increasingly crowded field of centrist Democratic organizations.

Third Way founders are focusing on the Senate — the last place elected Democrats have any say. And to do that, they’re trying to get corporate interests to cooperate on a legislative agenda that can help boost the party.

“Because we’re more moderate, we’re reaching out to industry and getting ideas from them,” said Matt Bennett, a co-founder of Third Way. “Progressives have done a pretty lousy job of even talking to the business community.”

Joining Bennett at the organization are President Jonathan Cowan and Policy Director Jim Kessler. The three met at Americans for Gun Safety, a group that sought to carve out a moderate position on gun control by arguing for ownership rights while also backing tighter restrictions on assault weapons and gun shows.

Bennett said the three felt with that issue, they had found “a real middle on an issue that had been polarized. We felt like we had a model that worked.” And the model became the basis for Third Way.

If corporate membership is any key, the organization is off to a rousing start. Though it’s barely out of the gates, the group has already recruited about 40 sponsors — including such business stalwarts as the U.S. Chamber of Commerce, the American Petroleum Institute, the Pharmaceutical Research and Manufacturers of America, insurance giant AIG and BellSouth. Most of these members ponied up $25,000, and with the help of some individual contributors, the group has managed to secure a $2 million budget for its first year.

So far, with business-backed Republicans controlling both chambers of Congress, long-stalled class-action and bankruptcy reform bills passed easily into law.

While Democrats and allied outside groups largely looked on, Third Way waded into the class-action debate, surprising some Democrats by circulating letters that supported passage of the measure.

“The objective is to carve out a different niche,” said Chad Jenkins, who works closely with Third Way as one of two Democratic lobbyists on the chamber’s 15-member team. “They’re showing, by doing these things, there’s a different Democratic Party than most people think.”

Bennett added, however, that the group’s real battles lie ahead. The group is working to hatch its first legislative package this month, which will address military preparedness. That effort will test the organization’s founding purpose — to not just spawn ideas and float them out into the ether as a think tank would, but rather to go a step further and actually work to pass bills.

The aim, Bennett said, is to help Democrats achieve some parity with their Republican counterparts, who have invested tens of millions of dollars in the past three decades building “a very large, well-integrated, enormously well-financed idea industry.”

They’ve got a very efficient pipeline that takes their material and sends it into Congress in the form of legislation and messaging,” Bennett said. “On our side, we have some very good and effective think tanks, but they’re far less integrated. An article in the Atlantic Monthly is prestigious, but it’s a tree falling in the forest unless somebody in a position to do so picks it up and turns it into action.”

Third Way is a 501(c)(4) group — a tax-exempt status that allows unlimited donations without having to disclose its donors. And it can only lobby for issues, as long as they are deemed to be in the public interest. Supporting candidates is out of bounds.

Bennett said sponsors so far have refrained from asking them to put Third Way’s face on clearly self-interested campaigns.

“We made clear to all of them when we recruited them to join our committee that we are not going to be carrying their very parochial water,” Bennett said. “And it’s been striking to me that they really get that. Nobody’s asked us to lobby on a tax provision. And, in fact, they know we’re not going to go to our Senators simply as their lobbyists.”

But when Third Way gets ready to lobby, it can rely on its built-in support from K Street, its long list of corporate backers and its support of advisory board members who serve in the Senate. They include Democratic Sens. Blanche Lincoln (Ark.), Evan Bayh (Ind.), Tom Carper (Del.), Mary Landrieu (La.), Mark Pryor (Ark.) and Ken Salazar (Colo.).

Notably, five of those six Democrats represent states that went to Bush in 2004. And each of the six fits squarely into the tradition of youthful, consensus-minded leaders like former President Bill Clinton, who bequeathed the new group its name when he sought “third way” solutions that straddled conservative and liberal orthodoxies.

But given the increasingly bitter partisan atmosphere in the Senate, with both sides bracing for an unprecedented standoff over judicial nominees, some downtown Democrats uninvolved with the organization expect it to struggle to find a role.

“It’s going to be tough for them to demonstrate their relevancy,” said one Democratic lobbyist. “The way the Senate’s functioning right now, there’s not a lot of bipartisanship. We’re almost halfway through the year, and we’re going to be in the appropriations cycle soon. For me, at least, for [a sponsorship of] $25,000, you’ve got to come up with something more marketable than goals to have down the road.”

But those involved with the group counter that it’s too young to fairly judge the effort. And considering its brief existence, they argue, Third Way has already been highly active.

The group holds monthly lunches with the chiefs of staff of its Senate co-chairmen, and its corporate sponsors are invited to participate in weekly meetings of working groups that address health care, telecommunications, energy and other issues.

“You can actually sit with other companies in the room, and you can actually have a full understanding of where they’re coming from and come together on a common agenda,” said Honeywell lobbyist Tim Keating, a Democrat.

He said he sees his company’s membership in the group not as a means to advance a political agenda but as “just another venue to have your voice heard.”

One lobbyist said, “Part of the attraction is you’re not using your PAC dollars. So it’s just like membership in a trade association, or the Business Roundtable, or the chamber.”

Other corporate sponsors have the opposite view. They say they don’t see an immediate benefit for their companies, but they support the group because they believe in its goals of promoting sober-minded debate and advancing progressive Democratic causes.

One Democratic lobbyist said he encouraged his company to back Third Way because “I think its good to have two thriving political parties that talk instead of scream.

“I’m also a Democrat,” he added, “and I want to see my party succeed.”

As the Third Way comes into its own, it has been careful to pay homage to its forebears on the centrist think tank scene and avoid predictable chatter about rivalries.

The group received the blessing of Al From, president of the Democratic Leadership Council, at an event during the 2004 Democratic National Convention in Boston. He helped host the event to introduce Democratic lobbyists at the convention to the then-nascent Third Way.

Helping cement the alliance, Third Way last month hired Bill Andresen, a former vice president and now an informal adviser to the DLC, to work as a senior adviser.

Andresen, a senior vice president at the lobbying firm Dutko Worldwide, said he sees the groups as having distinct purposes.

The DLC and its think tank, the Progressive Policy Institute, is “more of a big-picture organization,” while the Third Way is “more involved in translating those ideas into specific legislation.”

The most likely point of tension is that the two groups are inevitably working off similar fundraising lists. One Democratic lobbyist reported sending a DLC fundraiser into a frenzy after the lobbyist inquired about differences between the two groups, and about why a company should contribute to both.

Asked about the episode, Bennett downplayed it.

“If they had talked to … anybody senior at the DLC, they would have told them, ‘This is part of the movement, and we want to grow the movement, so we hope you give to both,’” Bennett said. “We’ve been very careful when people bring that up that we don’t want you to take away from the DLC to give to Third Way. That would not be helpful.”