Rep. Paul Hodes (D) will announce his candidacy for the Senate in New Hampshire later this week, The Hill confirmed Tuesday.

In a move quickly following Sen. Judd Gregg's (R-N.H.) nomination to become Secretary of Commerce in the Obama administration, Hodes will seek the Democratic nomination to run against either Gregg's successor in the Senate, or another Republican candidate in the Granite State.

The announcement will come late this week, after New Hampshire Gov. John Lynch (D) names Gregg's successor in the Senate. Lynch agreed to name a Republican to maintain the partisan balance in the Senate, and is expected to name J. Bonnie Newman, a former chief of staff for Gregg, to the seat.

Hodes sped up the timeline for his announcement following Gregg's appointment, an unexpected development in the Democrat's plans, the New Hampshire Union Leader reported Tuesday.

Hodes had said he was "seriously considering" a bid to challenge to Gregg before he was tapped to become Commerce Secretary in the Obama administration.

Instead of facing Gregg, a three-term incumbent in the Senate and scion to a New Hampshire political dynasty, Hodes will be pitted against a different Republican candidate in 2010.

Republicans will be left another open seat in New Hampshire following Gregg's departure, adding to the list of seats in politically competitive states the GOP will be forced to defend in the 2010 midterm elections.

Aaron Blake contributed to this report.