Rep. Dennis Hastert to Resign Early From Congress

Former House Speaker Dennis Hastert will resign his seat in Congress later this year, and not serve out the remainder of his term, FOX News has learned.

The Illinois Republican has informed the House GOP leadership of his early departure, according to Republican sources. No date has been chosen for a formal announcement, which was originally scheduled for Thursday, sources told FOX News, but the resignation is expected to become effective in December or January.

Hastert's leaving in the middle of the 110th Congress means his Illinois district will have to hold a special election, one more likely to favor a GOP candidate since the party is expected to be more adept at turning out voters in a low-turnout special election.

The 11-term congressman announced on Aug. 17 that he will be stepping down, but did not say whether it would be at the end of the session or before then. He is one of 12 Republican lawmakers to announce their retirements this year.

Hastert has taken a back seat in his party since stepping down from its leadership earlier this year. Having become House speaker in 1999 following the resignation of Newt Gingrich, he went on to be the longest-serving Republican speaker of the House. Hastert was succeeded this year by Rep. Nancy Pelosi, D-Calif., after Republicans lost control of the House in last November's elections.

FOX News’ Major Garrett contributed to this report.