Even though Democrats have carried the Gopher State in eight consecutive presidential elections dating back to 1976, and 16 of the past 19, Minnesota has rightfully earned its reputation as a purple battleground state when it comes to presidential politics.
Despite the Democratic dominance, the margin of victory in presidential elections has been historically slim in Minnesota in recent generations, and overall quite competitive.
In the state's first 20 votes for president, from 1860 to 1936, only 3 races were competitive—decided by 10 points or less (1892, 1912, and 1916). An equal number of elections decided by more than 30 points (Teddy Roosevelt's 55-point victory in 1904, Warren Harding's 51-point victory in 1920, and FDR's 31-point victory in 1936). The average margin of victory in Minnesota across these twenty elections was a large 22.8 points.
By contrast, during the past 17 elections (1940-2004) 10 of the 17 races were competitive, with an average margin of victory of just 8.8 points across these 17 races. In fact, although Republicans lost each race, the GOP Republican nominee has been competitive in 5 of the past 7 races since 1980, losing by an average of just 6 points.
The Democratic dominance in the face of a continuing pattern of highly competitive races is quite unusual—it is surprising the GOP has not broken through with victories more often. Democrats are currently favored again in 2008—with Hillary Clinton, Barack Obama, and John Edwards all leading in match-up polls against the leading Republican candidates.