By John Whitesides

WASHINGTON (Reuters) - U.S. Democrats renewed a
traditional election-year battle over Social Security
Friday, launching a campaign to warn seniors that Republican
proposals would undermine the popular retirement program.

Democrats said Republican plans to let seniors invest some
of their Social Security funds in the stock market would
threaten retirees' financial security.

"The Republicans advocating these changes are not friends
of senior citizens," Democratic National Committee Chairman Tim
Kaine said ahead of Saturday's 75th anniversary of President
Franklin Roosevelt's signing of the Social Security law.

Democrats plan events around the country to celebrate the
anniversary and highlight Republican candidates who have called
for some form of privatization of Social Security.

Republicans said the attacks were designed to put the focus
on something other than President Barack Obama's economic
failures as Democrats struggle to keep their majorities in
Congress ahead of the Nov. 2 elections.

"Democrats in Washington are desperate to shift attention
away from their reckless spending record and failure to create
jobs," said Brian Walsh of the Republican Senate campaign
committee.

A report last week said Social Security would exhaust its
reserves in 2037, but lawmakers have been unable to find ways
to boost the program, battling over proposals to cut benefits,
hike taxes or raise the retirement age.

Republican President George W. Bush's push to add personal
retirement accounts failed in 2005 in the face of heavy
Democratic and public opposition. Democrats said it would be
more foolish now after the upheavals and mood swings on Wall
Street in recent years.

The issue has been particularly prominent in Nevada's
senate race. Democratic Senate leader Harry Reid has attacked
Republican opponent Sharron Angle, a favorite of conservative
Tea Party groups, for saying Social Security should be phased
out for "something privatized."

After taking heavy fire on the issue, Angle released a
television ad this week attacking Reid for raiding the Social
Security trust fund "for his own pet projects" and saying she
would like to save the program.

Democrats have made Social Security a top issue for years,
and at times have had success painting Republicans as a threat
to the popular program, particularly in the 1980s.

A poll released earlier this week by NBC and the Wall
Street Journal found Democrats had an advantage of 4 percentage
points over Republicans when voters were asked which party
would do the better job on Social Security -- the smallest lead
listed in the poll since 1994.

Senior citizens traditionally are the most active voters,
and their participation could be crucial in a low turnout
mid-term election that does not feature a presidential contest
to attract less interested voters.
(Editing by Jerry Norton)