Romney Carries Illinois Primary with Lowest Ever Winning Percentage

The former Massachusetts governor becomes one of just three winners in 100 years of the primary to fail to reach the 50 percent mark

Mitt Romney blunted another potential Rick Santorum surge Tuesday with a win in Illinois, giving his campaign a third consecutive victory in the East North Central division of the Midwest – following his previous narrow victories in Michigan and Ohio.

Compared to Ohio (0.9 points) and Michigan (3.2 points), Romney’s double-digit victory in Illinois was relatively comfortable.

However, when viewed through the lens of history, the former Massachusetts governor’s victory in the Prairie State reveals he turned in some of the least impressive numbers ever tallied for a winner of the state’s 100 year-old primary.

A Smart Politics study of Illinois Republican primary election returns finds Mitt Romney was victorious with the lowest percentage of the vote in the 26 cycles of the primary dating back to 1912.

With 99 percent of precincts reporting, Romney carried the state with just 46.7 percent of the vote – the lowest winning total in 100 years of presidential primaries in the state.

Only two other winners of the state’s GOP primary have failed to win a majority of the vote: Ronald Reagan in 1980 (48.5 percent) and John McCain in 2008 (47.5 percent).

With Rick Santorum coming in second at 35.0 percent, Romney’s margin of victory was also historically quite narrow.

The 11.7-point Romney Illinois win is tied for the second most narrowly decided finish across the 26 cycles of the state’s presidential primary.

Only publisher Frank Knox’s 7.9-point win over Idaho U.S. Senator William Borah in 1936 was more closely contested in a state that has averaged 58-point victory margins over the decades.

The Romney win was tied with and Reagan’s 11.7-point victory over Illinois Congressman John Anderson in 1980.

In terms of raw vote, with a few precincts yet to report in Cook County as well as all of Macoupin County, the 2012 contest appears to be slated for the fifth largest turnout in state history.

With more than 917,000 votes tallied to date, only the primaries of 1952 (1.27 million), 1928 (1.18 million), 1980 (1.12 million), 1940 (977,777), and 1924 (919,082) had more voters, with this year’s contest likely to overtake the latter.

Romney did decidedly better in Illinois than his father, George Romney, some 44 years ago. The elder Romney came in 7th place with 16 write-in votes in the state’s 1968 primary – three and a half months after exiting the race in February.

Smallest Winning Percentage in Illinois Republican Primary, 1912-2012

Year	Winner	%	MoV
2012	Mitt Romney	46.7	11.7
2008	John McCain	47.5	18.9
1980	Ronald Reagan	48.5	11.7
1920	Frank Lowden	50.5	16.5
1936	Frank Knox	53.7	7.9
1988	George H.W. Bush	54.7	18.7
1924	Calvin Coolidge	58.0	16.0
1976	Gerald Ford	58.9	18.8
1912	Teddy Roosevelt	61.1	31.9
1964	Barry Goldwater	62.0	36.7
1996	Bob Dole	65.1	42.3
2000	George W. Bush	67.4	45.9
1952	Robert Taft	73.6	61.4
1992	George H.W. Bush	76.4	53.9
1968	Richard Nixon	78.1	68.4
1916	Lawrence Sherman	90.1	81.2
1944	Douglas MacArthur	92.0	85.7
1956	Dwight Eisenhower	94.9	90.8
1948	Riley Bender	96.9	94.9
1972	Richard Nixon	97.0	95.5
1928	Frank Lowden	99.4	99.0
1932	Joseph France	99.4	98.9
1940	Thomas Dewey	99.9	99.9
1960	Richard Nixon	99.9	99.9
1984	Ronald Reagan	99.9	99.9
2004	George W. Bush	100.0	100.0
—	Average	75.8	57.9

Table compiled by Smart Politics from data culled from the Illinois Secretary of State and Illinois State Board of Elections.

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