Sen. Blanche Lincoln on Wednesday asked for, and received, assurances of support from her Democratic colleagues as she prepares for a June 8 primary runoff against Arkansas Lt. Gov. Bill Halter — although it remained unclear what form that assistance might take beyond campaign contributions.

Halter and a third candidate held Lincoln to 45 percent of the vote in Tuesday’s Senate Democratic primary, short of the 50 percent she needed to avoid a runoff and advance to the general election. Democratic Senators responded with hearty pledges of backing in the runoff against the upstart lieutenant governor, whose candidacy was fueled by organized labor and liberal activist groups.

But the extent of that support was vague as the three-week sprint to Election Day got under way.

“I’m for Sen. Lincoln, I’ve been that way from day one and that won’t change. I think she’s done a good job for Arkansas,” Sen. Mark Pryor (D-Ark.) said. “We have a good working relationship, and I’ve been trying to help her all along.”

Pryor sidestepped specific questions of what forms of support he would offer. Pryor, who is not on the ballot this cycle, has not seen his image diminish at home the way Lincoln’s has. Pryor’s father was a well-liked Senator before him, and his name has cachet in the Natural State’s strong Democratic Party machine.

Democratic Senatorial Campaign Committee Chairman Bob Menendez (N.J.) was similarly ambiguous when asked Wednesday about plans for helping Lincoln. DSCC spokesman Eric Schultz maintained the committee’s long-standing practice of not disclosing whether — or how, when and where — it plans to spend money and deploy personnel. However, Schultz confirmed that Lincoln has the DSCC’s strong support.

“We support our incumbents, and Sen. Lincoln is no exception,” he said.

Meanwhile, Lincoln was in Washington, D.C., on Wednesday for votes on the financial regulatory reform package. A Lincoln spokeswoman said the Senator during the three-week runoff campaign plans to be in the nation’s capital for votes and to attend to other Senate matters.

“As she has throughout the primary election period, Sen. Lincoln will continue to balance her full-time duties standing up for Arkansas in the Senate and campaigning at home,” campaign spokeswoman Katie Laning Niebaum said.

Sens. Claire McCaskill (D-Mo.) and Jeanne Shaheen (D-N.H.) said Lincoln received an outpouring of support from the caucus Wednesday, adding that their backing would likely include financial contributions.

“I think she’s reaching out to the caucus,” McCaskill said. “Financially, this is tough. There’s been a lot of money spent on her opponent. I think she’s reaching out for financial help to fellow Senators.”

Washington lobbyists were also expecting to receive appeals for financial assistance from Lincoln’s campaign.

Senate Democrats, struggling to reach final agreement on a financial regulatory reform bill that Lincoln helped craft, expressed sympathy for the predicament the second-term incumbent finds herself in. Democrats understand the anger and anxiety of voters given the tough economy and events of the past year, if not past several years, and have hinted that many of their colleagues are bearing the brunt of that, deserved or not.

Democrats, at least in the Senate, note that Lincoln has voted with President Barack Obama on health care reform and nearly every major issue to come before the Senate since he took office. In fact, Lincoln has taken a harder line on the derivatives regulation portion of financial regulatory reform — and refused to back down — than some of her Democratic colleagues.

“People today were very committed to doing everything we can to not only help her win her runoff, but to win in November,” Shaheen added.

Lincoln was already among the most vulnerable Democratic Senators of the 2010 cycle against hypothetical Republican competition in the November general election when Halter jumped into the Democratic primary. He was given little chance by the Arkansas Democratic establishment, given that he challenged her from the left in this conservative leaning state.

But Halter finished with a strong 42.6 percent of the vote, just two points behind Lincoln, while businessman D.C. Morrison garnered 13 percent. Rep. John Boozman (Ark.) won the Republican Senate primary outright and awaits the winner of the Lincoln-Halter runoff.

The same Tuesday night Lincoln found herself unable to close out the Arkansas primary, Sen. Arlen Specter lost his Democratic primary battle with Rep. Joe Sestak in Pennsylvania. Additionally, Senate Minority Leader Mitch McConnell’s handpicked candidate lost the GOP primary in the race for Kentucky’s open Senate seat, all of which added to the sense that this is a bad year to be a Washington incumbent.

One thing Lincoln can count on in the short campaign is the help of Arkansas’ Democratic establishment, although whether it makes a difference was unclear at the outset of the race. In Pennsylvania, Specter’s monopoly over the Democratic establishment, which in his primary campaign included organized labor, was ultimately not enough to win.

“I think you’ll see the Democratic establishment lend her its support,” an Arkansas-based Democratic operative said. “What that means, I don’t know.”