In a big boost for Ann McLane Kuster’s campaign, the Democratic congressional candidate this afternoon will receive the endorsement of EMILY’s List, a powerful pro-choice political action committee dedicated to electing Democratic women to federal and state political offices.

EMILY’s List was active in helping Sen. Jeanne Shaheen and Rep. Carol Shea-Porter get elected last year, and Kuster will become only the third candidate for an open congressional seat the group has endorsed in the current election cycle.

Shea-Porter, who is a candidate for a third term, also received the endorsement of the organization earlier today.

Kuster “is clearly the strongest candidate to keep this seat in the Democratic column,” Emily’s List president Ellen Malcolm said in a statement. Kuster said she was "thrilled" to get the endorsement.

It’s no surprise that Kuster would receive the EMILY’s List endorsement, but the timing was unexpectedly early. Sources say it had originally been slated for after the first of the new year but was moved up to help Kuster continue to build momentum.

It comes after Kuster had a strong showing in her third quarter campaign finance report, raising $180,000. It comes after potential Democratic congressional primary rival Katrina Swett, who has not been supported by pro-choice groups in the past, put off indefinitely her end-of-October deadline to announce whether she will run for the open seat. And it comes after state Senate President Sylvia Larsen announced that she won’t run for the seat, which is being vacated by Rep. Paul Hodes, who is running for the U.s. Senate.

EMILY’s List is a national political action committee that focuses on "bundling" contributions, often small ones, and funneling them to candidates it endorses. Many of the contributions are below the $200 federal limit that require individual reporting.

The group says that in the 2007-2008 election cycle, it raised more than $43 million to recruit and support women candidates.

Correction: When first posted, this article misstated Katrina Swett's position on abortion.

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