President Obama is gunning for a "grand bargain" to end the political impasse over raising the federal debt ceiling. But with only 25 days left until the U.S. defaults, he has to step over some perilous land mines to secure a deal. Republicans are refusing to accept any tax increases, but Obama is also facing stiff resistance from liberals over his reported inclusion of Social Security cuts, and maybe even Medicare tinkering, in the big deal. And the Left is right, says Paul Krugman in The New York Times. If Obama keeps insisting on parroting "the Right's favorite economic fallacies," Democrats should protest. Will they?

Liberals may well oppose Obama: Democrats, especially House progressives, are getting fed up with having to swallow Obama's bad deals, says Joan McCarter at Daily Kos. And in this case, it's not only a bad idea to cut Social Security benefits, but nonsensical to include it in a deficit-reduction deal: "Social Security isn't adding to the deficit." So yes, if Obama gives away too much again, Democrats are "willing to vote against their president" this time.

"House Progressive Caucus opposed to Social Security's inclusion..."

Democrats can save their outrage: "The Left naturally is squealing about Obama stabbing them in the back," says Allahpundit at Hot Air. But Obama's almost certainly bluffing about slashing entitlements. And if liberals were savvier, they'd play along with the Grand Bargain charade: It would be "smart politics" to grab a piece of "the 'deficit hawk' label," knowing Republicans will scuttle any deal before they ever "cave on taxes."

"Are they seriously going to cut entitlements...?"

Don't forget, the Left has leverage: "Nancy Pelosi hasn't had very many opportunities to influence policy" this year, says Nate Silver at The New York Times. But when you read the various proposals being floated, remember that "the views of liberal Democrats are far more than a token issue" this time around. Faced with Tea Party opposition to raising the debt ceiling, period, House Republicans will need the votes of not just Democrats, but liberal Democrats, to pass any deal.

"Liberal Democrats have leverage on debt deal"