Pressure is mounting on President Obama to intervene to fix the ever-worsening backlog of disability cases at the Department of Veterans Affairs or replace the head of the agency.

With half VA's backlogged cases now more than a year old, a bipartisan group in Congress last week sent a letter to the president asking that he get directly involved.

That letter, which stops short of calling for the removal of VA Secretary Eric Shinseki, was signed by 26 congressmen who are military veterans or active members of the National Guard or Reserves.

Meanwhile, the advocacy group Concerned Veterans for America (CVA) called on Obama to remove Shinseki in a new 30-second Web video, citing his failure to bring the backlog of disability cases under control. CVA is the first major national veterans organization to call for Shinseki's removal.

"The VA is clearly on the wrong track," the letter from the House members, including two Democrats, reads. "Mr. President, we know you care deeply for America's veterans, but it is important for you - as Commander in Chief - to publicly acknowledge the problems within VA and the necessity for reforms and leadership that are capable of alleviating the claims backlog and improving the benefit delivery system."

The two Democrats who signed the letter, Reps. John Conyers of Michigan and Bobby Rush of Illinois, would not comment further to The Washington Examiner.

Rep. Duncan Hunter, R-Calif., is the only member of Congress thus far to call publicly for Shinseki's ouster. After he made that demand earlier this month in a Washington Post opinion column, Hunter was contacted by other House members who later signed last week's letter.

"The congressman's call for a change in leadership prompted many members of Congress to express support for improvements and accountability, so the letter reflects the position that the president needs to step in to address problems within VA that evidently can't be fixed in-house," said Joe Kasper, Hunter's deputy chief of staff.

VA considers a claim backlogged if it has taken longer than 125 days to issue a rating, which determines whether a veteran is entitled to benefits for injuries or illnesses tied to military services.

When Shinseki took office in 2009, he promised to eliminate the backlog by 2015, and testified in recent congressional hearings the agency is still on track to meet the goal.

But since 2009, the percentage of cases that are backlogged has doubled to about 70 percent of all claims, according to VA figures. It took an average of 161 days to rate a claim in 2009. Today it takes about 291 days.

Roughly half of the backlogged claims have lingered longer than a year, according to new figures issued last week by the VA.

Of the nearly 600,000 backlogged cases, almost 253,000 have been in the system more than a year. There are also 41,863 claims that are more than two years old, according to VA figures provided to the Examiner.

Those numbers show a failure in leadership, said Darin Selnick of CVA. Firing Shinseki will not solve the problem, but it will signal that VA leaders will be accountable for their failures, he said.

"The problem is much bigger than Shinseki," said Selnick, who was special assistant to three VA secretaries under former President George W. Bush. "But Shinseki has become part of the problem, not part of the solution."

The White House press office did not comment on calls for Shinseki's ouster. Earlier this month, Obama spokesman Jay Carney called the backlog "unacceptable" and said eliminating it is a "national priority."

"The president has been clear that he expects results," Carney said at the April 15 press briefing. "This administration is engaged in an all-out effort to complete this critical mission. The president is kept abreast of this problem regularly. It's one he considers a significant priority of his. And he is very impatient for results."

Mark Flatten is a member of The Washington Examiner Watchdog investigative reporting team. He can be reached at