The filing deadline for candidacy papers closed last week in Madison and Democrats, who took control of the state Senate in 2006, appear poised to do the same in the Assembly in 2008.

Republicans will face an uphill battle holding onto their current 5-seat majority in the lower legislative chamber (52 to 47). Republicans have controlled the Assembly since the election of 1994, and their advantage grew with every election cycle from 1994 (3 seats), to 1996 (5 seats), to 1998 (11 seats), to 2000 (13 seats), to 2002 (17 seats), to 2004 (21 seats). In 2006, however, that advantage fell to just 5 seats after the Democrats gained 8 seats (Smart Politics projected a 7-seat gain for the minority party).

Assuming, for the moment, that all incumbents facing primary challenges in September will be victorious, Republicans will have 46 incumbents on the ballot, compared to 42 for the Democrats. Republicans, however, will need to defend twice as many seats that were competitive in 2006 (16 districts) than will the Democrats (8 districts). (Competitive races are defined as those decided by 10 points or less in the previous election cycle).

Secondly, Republicans will have to defend one more open seat (6) than the Democrats (5) and three of these open seats are located in competitive districts (#47, 57, and 92). None of the open Democratic seats were competitive districts in 2006.

Thirdly, Democrats will also run more than one-quarter of their incumbents (11) without a challenger from the GOP. Republicans, meanwhile, will only run 3 of their 46 incumbents free from the challenge of a Democratic candidate.

If the Democrats net just 3 seats in November, and maintain their advantage in the state Senate, they will control both the legislative and executive branches of government for the first time in Wisconsin since the 1984 election cycle.