A pair of powerful Washington, D.C.-based interest groups and one of the city’s most prominent conservatives announced new Congressional endorsements during a snowy Tuesday in the nation’s capital.

First, the pro-abortion-rights group EMILY’s List announced that it was endorsing Terri Sewell (D) in the crowded open primary in Alabama’s safely Democratic 7th district.

“As a successful attorney and community leader, Terri has dedicated herself to making life better for all Alabamians,” said Stephanie Schriock, president of EMILY’s List, in a statement Tuesday. “As a candidate, she’s focused her campaign on economic development that will create jobs and opportunity for hard-working Alabama families. Those are the qualities that will set her apart in this crowded field of candidates in the June Democratic primary.”

Sewell’s top opponent in the race to replace Rep. Artur Davis (D) — who is running for governor — appears to be state Rep. Earl Hilliard Jr. (D), the son of ex-Rep. Earl Hilliard (D), who was ousted by Davis in a 2002 primary.

Meanwhile, the political action committee for the anti-tax group Club for Growth announced its own endorsements in two open-seat races that Republicans are expected to hold in 2010.

The club is supporting former state Republican Party Chairwoman Robin Smith in Tennessee’s 3rd district and businessman Mike Pompeo in Kansas’s 4th district.

“Mike Pompeo and Robin Smith are exactly what Washington and America need right now: honest, principled leaders who realize that big government is the problem, not the solution,” said club President Chris Chocola.

Americans for Tax Reform President Grover Norquist also jumped into the endorsement fray on Tuesday. Norquist announced that he is backing former state Speaker Marco Rubio in his bid for Florida’s open Senate seat. Rubio is locked in a high-profile primary against Florida Gov. Charlie Crist.

“I have followed Marco Rubio’s career very closely and am proud to support him in his bid for U.S. Senate,” Norquist said. “In closely examining his record, I remain convinced he has been the most courageous, pro-taxpayer legislative leader in the country and will continue this path in the U.S. Senate.”