Sens. Barack Obama and Hillary Clinton will compete Saturday for 161 delegates in Washington state, Louisiana and Nebraska, followed by Sunday's Maine caucuses with 24 delegates.
Obama was campaigning in all four states; Clinton planned stops in Washington -- where the weekend's biggest contest will occur -- and Maine.
Analysts have pointed to Obama's strong performances in past caucuses as well as an infusion of post-Super Tuesday cash as giving the Illinois senator an advantage going into the weekend.
In Washington, Obama was endorsed this week by the state's biggest labor union, the Service Employees International Union. On Friday, Gov. Chris Gregoire offered him a last-minute endorsement even though the state's U.S. senators, Patty Murray and Maria Cantwell, and other prominent female leaders are in the Clinton camp.
Political scientist Bryan Jones of the University of Washington said to the Associated Press of Evergreen State voters: "They're Obama-crazy here, even the Republicans."
Despite the Obama-mania, Clinton has garnered the support of some critical organizations in the state including the 25,000-member International Association of Machinists and Aerospace Workers.
Washington state voters don't register by party, which could draw some social conservatives into the Democratic fray.
"With McCain now a shoo-in, some who would normally vote in the Republican race might be drawn to the higher-stakes Democratic contest," the AP reported.
Meanwhile in the Republican stronghold of rural Nebraska, Chelsea Clinton campaigned for her mother, taking questions for an hour from students in Lincoln. Many asked about Sen. Clinton's efforts to establish universal health care -- her failure in the 1990s and her renewed plans now.
"It's not how people react when they succeed but how they react when they fail," Chelsea Clinton responded. "She learned from that experience."
Usually a quiet presence with her mother on the trail, she planned to meet students in Omaha on Friday.
Obama told a crowd of 10,000 at an Omaha arena Thursday: "You're here because you don't want to just be against something. You want to be for something."
Looking ahead, Obama and Clinton will vie Tuesday for 168 delegates in Virginia, Maryland and Washington, D.C. -- a one-day bonanza dubbed the "Crab Cake Primary" by NewsHour commentator Mark Shields.
The biggest prizes on the horizon are still the March 4 contests in Ohio and Texas.
However, The Washington Post's Paul Kane warned on Thursday that the remaining Democratic contests may only help solidify the deadlock between the two candidates.
"If you review the delegate figures, you can only arrive at one conclusion: It is now basically mathematically impossible for either Hillary Clinton or Barack Obama to win the Democratic presidential nomination through the regular voting process (meaning the super-delegates decide this one, baby!)," Kane wrote.
After doing the math, he concluded: "If they both have 820 plus pledged delegates so far, they'll need to win roughly 1,200 -- 75 percent -- of the remaining 1,600 delegates to win the nomination through actual voting.
"In other words: Ain't gonna happen, barring a stunning scandal or some new crazy revelation."
If the Democratic race indeed is left to the whim of super delegates, that decision could shape their political careers.
"The political pros who make up the super delegates might want to wait for Ohio, Texas (both on March 4), and eventually Pennsylvania (April 22)," Newsday columnist James M. Klurfeld wrote. "But those pros, who want jobs in a new administration, know not only whom they choose but when they choose could determine where they sit come Jan. 20."
But the conjecture and political opining have only taken candidates so far this season, and the weekend's voting could help clarify where the two Democrats stand as they struggle for each delegate and every precinct.
