(CNN) – A coalition of progressive groups claiming to represent millions of Americans is planning a multi-state effort urging the expansion of Social Security benefits.
The Progressive Change Campaign Committee (PCCC) and Democracy For America (DFA say they will be joined by several other groups including MoveOn.org in putting out a series of TV and online ads planned for the near future.
A petition is already posted on the PCCC's website where signers can urge Congress to expand Social Security.
The petition and ad campaign are meant to bolster twin bills in the U.S. Senate proposed by Democrats Mark Begich of Alaska and Tom Harkin of Iowa.
An email sent to the progressive coalition's supporters claims the bills would give Social Security beneficiaries an additional $452 per year by age 75 and $807 per year by 85.
The bill would also eliminate the cap on how much of individuals' earnings can be paid into Social Security. Currently, Social Security contributions are limited to the first $113,000 of income.
Eliminating that cap is aimed at making the wealthy "pay their fair share," the email says.
Any attempt at expanding so-called entitlements is likely to draw a swift rebuke from Republicans who've resisted any and all additional spending. Republicans will soon be fighting a planned Democratic push to raise the government debt ceiling when Congress returns from its August recess.
A move to increase the income cap paid into Social Security will almost certainly face just as much backlash, as it's seen as a tax increase.
Harkin will be retiring at the end of this term, his fifth in the Senate. Begich on the other hand faces a stiff reelection fight in a Republican-leaning state.