Veteran Sens. Blanche Lincoln and Arlen Specter could find themselves out of a job at this time next week, the victims of restless Democratic primary voters and activists who no longer take their cues from the national party establishment in Washington.

Unlike the previous two election cycles, when Democratic leaders on Capitol Hill cleared the field for their incumbents and muscled preferred primary candidates to the nomination in targeted seats, 2010 has witnessed a dramatic slide in party influence beyond the Beltway. Not only are the Arkansas and Pennsylvania incumbents vulnerable in primaries, but the Democratic Senatorial Campaign Committee’s hand-picked candidate in North Carolina also is in trouble.

Democrats cite a variety of factors including voter anxiety over the struggling economy, the expectations of their base versus what they have delivered and the lack of a galvanizing political enemy in former President George W. Bush. Democratic Senators and strategists argue that the midterm campaign is anti-incumbent across the board, although they concede that their party faces political headwinds with unique challenges.

“I think it is certainly easier to be unified when you’re in the minority. When you’re in the majority, then you’re making the tough decisions about governing,” said Sen. Debbie Stabenow (D-Mich.), who won a second term in 2006. “It’s just a sign of the times.”

“I think it’s a different climate. It’s hard. You have a recession,” added Senate Democratic Conference Vice Chairman Charles Schumer (N.Y.), who as DSCC chairman in 2006 and 2008 exerted considerable influence over party primaries and protected all of his incumbents on the way to winning 14 seats. “It’s easier to achieve a goal than maintain a goal.”

The inability of Washington Democrats to shape the political playing field has grown more acute with the onset of the primary campaign season. The first shot across the bow came Tuesday in West Virginia, where 14-term Rep. Alan Mollohan fell in the 1st district Democratic primary to state Sen. Mike Oliverio, who hit the incumbent for supporting health care reform on his way to a 12-point victory.

In Pennsylvania, Specter is fighting Rep. Joe Sestak (D) one year after leaving the Republican Party to avoid an uphill primary battle against former Rep. Pat Toomey. Specter was immediately embraced and backed by President Barack Obama, and the DSCC is now working overtime to salvage his campaign. Specter is running even with Sestak after leading by wide margins just a few months ago.

Pennsylvania Sen. Bob Casey said he expects Specter to win Tuesday’s primary, adding that the incumbent is working hard and always expected a tough race. Casey won a contested Democratic primary in 2006, but his nomination was never in doubt after Schumer worked to clear out any serious competition.

“When you have an economy like we have — even though it’s a recovering economy — there’s going to be plenty of volatility, and you’ve seen some of that play out in our state and across the country,” he said.

In Arkansas, Lincoln is under threat from Lt. Gov. Bill Halter. Liberal groups are upset with positions Lincoln took during the health care reform debate and are spending mightily to make her second term her last. If Lincoln survives Tuesday’s primary in her state, she will head into the Nov. 2 general election as one of this cycle’s most endangered Democrats.

Sen. Mark Pryor chalked up Lincoln’s primary challenge mostly to labor unions and Democratic activist groups from outside the state. The Arkansas Democrat conceded that there are some disaffected liberals, but he said such voters make up a small part of the electorate in his conservative-leaning home state. “This is a MoveOn.org and a labor union thing,” Pryor said, adding that he expects Lincoln to win the primary and general election.

Lincoln said the difficult environment for Democratic incumbents, including in some primaries, is the result of these elections being midterm contests occurring in the first term of a new administration. The Senator hinted that some of her political difficulties stem from a voter backlash to Obama administration policies, noting that her predicament this year is not unlike what she faced as a House incumbent during the midterm campaign of 1994.

“People’s expectations are always elevated during a presidential year because there’s lots of things going on and lots of promises being made. When you look at those expectations and promises that have been made and you look at the reality of how Washington works, it’s unfortunate, because there’s no way you can ever meet those expectations,” Lincoln said. “And when you run in a midterm of a new administration, you’re the first thing that comes between the folks and their expectations that haven’t been met.”

Meanwhile, in Hawaii, Sen. Daniel Inouye has failed at his usual role of Democratic kingmaker.

In a special election to fill the vacant 1st district seat, Inouye and the Democratic Congressional Campaign Committee clashed over which candidate should receive the party’s backing, with the Senator and the labor unions backing Colleen Hanabusa and the DCCC throwing its weight behind former Rep. Ed Case. This has positioned Honolulu City Councilman Charles Djou (R) to win the May 22 contest.

Inouye downplayed the imbroglio, saying the intraparty feud was overblown because of a “more active media,” and that the situation “demonstrates that the Democratic Party is democratic.”

In the Tar Heel State, former state Sen. Cal Cunningham, recruited by the DSCC specifically to challenge Sen. Richard Burr (R), finished second in the May 4 Democratic primary to Elaine Marshall. Cunningham and Marshall appear to be running even heading toward their June 22 runoff.

The Republican establishment is not without its own problems. Last weekend, Sen. Bob Bennett failed to qualify for the June 22 Utah Republican primary ballot after finishing third in a vote of 3,500 of the state’s GOP nominating convention delegates.

And over the past several months, the Republican base in Florida and around the country slowly but surely rejected Gov. Charlie Crist — the choice of establishment Republicans in Washington to run for Senate in the Sunshine State — in favor of former state Speaker Marco Rubio. Crist has since dropped out of the GOP primary to run as an Independent, prompting the Members of the Senate Republican leadership to yank their endorsements.

Democratic political strategists argue that Democratic incumbents this year are dealing with an anti-Washington fervor dangerous to both political parties equally. They contend that it would be mistake to liken voter angst to the frustration in 2006 and 2008 that was focused mainly on the party in power in the White House.

Republican strategists agree, but only to a point.

“Beyond the primaries, this is a distinctly Democratic problem, as the focus will become their control of Washington and voter anger over the direction of the country,” said one Republican strategist who advises Congressional candidates.