The letter is from the American Energy Alliance, Heritage Action for America, the Competitive Enterprise Institute, the American Conservative Union, Freedom Action, and American Commitment.
The wind credit offers 2.2 cents per kilowatt-hour for wind power production. It has been extended a handful of times since Congress instituted it in 1992, but it will expire Dec. 31 without another extension.
Many Republicans in the 21 states that lack a renewable electricity standard already have asked House Speaker John Boehner (R-Ohio) to nix the incentive.
Those state electricity standards set mandates for the amount of power generated from renewable sources.
The states without such incentives are concentrated mainly in the Southeast, Appalachia and the Gulf Coast, and also generally have less installed wind power than states with renewable energy mandates.
For now, the credit’s fate is tied up in the ongoing “fiscal cliff” talks between Boehner and President Obama.
Still, its backers and detractors have been busy pressing their cases in the event those negotiations to avoid automatic spending cuts and income tax increases fail.
Some fiscal conservatives contend Congress should end the credit to help close the deficit, pointing to the one-year extension’s $12.1 billion price tag through 10 years.
Industry trade group the American Wind Energy Association has said it eventually wants to phase the credit out, but that ending it now would be too abrupt.
Most Democrats and some Republicans in both chambers have voiced support for the credit extension, calling it a boon for economic growth.
And with 81 percent of wind installations residing in GOP districts, many Republicans have voiced support for the credit as well — though a good many also oppose or have not weighed in on the incentive.
This post was updated at 9:22 a.m.