Minutes after Sen. Dean Heller (R-Nev.) was sworn in to office Monday afternoon, EMILY’s List announced it is endorsing his likely Democratic challenger in 2012, Rep. Shelley Berkley.

“Shelley Berkley has a great chance to be the first woman elected to the U.S. Senate from Nevada,” said Stephanie Schriock, the president of EMILY’s List. “The EMILY’s List community was proud to support her in the past, loves her fighting spirit, and is thrilled to help her make history now.”

Berkley, a Las Vegas-area Congresswoman, announced her campaign last month in what was then an open-seat race. However, the resignation of Sen. John Ensign’s (R) earlier this month paved the way for Heller’s appointment and gives Republicans a leg up in the race that is expected to be highly competitive.

Berkley launched her campaign with the backing of the Democratic Senatorial Campaign Committee, and now EMILY’s List is joining the Democratic chorus of support. Schriock said Berkley is a “passionate fighter, with a solid record of creating jobs and working hard for Nevada.”

A Public Policy Polling survey from late April showed Heller with a small, statistically insignificantedge over Berkley, 47 percent to 43 percent. The survey of 491 registered Silver State voters, taken April 21-24, has a margin of error of 4.4 points.

At least one other Democrat, attorney Byron Georgiou, has filed to run for the Senate seat, but Berkley is overwhelmingly favored to be the nominee.