Glenn Thrush of Politico has reported that labor unions are conducting an eleventh-hour campaign to pressure House Democrats into backing the Senate health-care bill. More specifically, they are targeting members who previously favored the pro-life Stupak Amendment. “In addition to the $11 million in TV and radio ad buys partly financed by labor cash,” Thrush writes, “local AFL-CIO affiliates will staff phone banks and visit members’ offices in districts with high concentrations of organized labor.”

In a related story, SEIU boss Andy Stern earlier this week told Steven Greenhouse of the New York Times that his organization is preparing to support independent challengers against anti-Obamacare Democrats. “If health care goes down and there are people who promised our members that they were going to vote for health-care reform — which for our members is a huge issue — if they aren’t going to stand up for what they said they were going to do, they shouldn’t be going back to Washington,” Stern declared.

(Chris Cillizza of the Washington Post has identified the five House Democrats who are “likely to come under the most intense pressure from both sides in this final week of lobbying.”)