According to Roll Call, Dennis Hastert will announce his resignation from the House tomorrow:
Former Speaker Dennis Hastert (R-Ill.) is expected to announce Thursday that he is resigning his seat in Congress effective later this year, eventually setting up a special election to succeed him, knowledgeable GOP sources said late Wednesday.
Rumblings have persisted for months that Hastert, who announced this summer that he would not seek re-election in 2008, was unlikely to complete his current term.
This week Hastert met with House Minority Leader John Boehner (R-Ohio) and was making calls to tell people of his decision on Wednesday morning.
The article also adds that, Illinois Gov. Rod Blagojevich has 5 days from Hastert's last day in office to set a date for the special election, which must take place within 115 days. Depending on the time line of Hastert's decision, we could see a special election coinciding with the state's February 5th primary. Stay tuned.
UPDATE: The Politico says that Hastert's announcement is postponed:
Hastert initially planned to make an announcement Thursday, but has since scrapped that decision, according to one GOP aide. The former speaker, who announced his plans to retire over the summer, is still expected to leave the House some time in December, but the date of his departure - as well as his announcement - remains unclear.