Which States Are Bellwethers for Partisan Control of the US Senate?

Two states – Rhode Island and Nevada – have elected U.S. Senators into the majority party of the subsequent Congress 75+ percent of the time over the last 100 years; Virginia has done so in each of the last six elections

In a midterm election cycle in which the balance of power in the U.S. House is not in doubt, the central question remains which party will control the U.S. Senate after the November elections.

A bevy of races have been highlighted that suggest – in the current political climate – the Republican Party will gain seats.

But will they gain enough?

As prognosticators lay out the odds for each of 2014’s key races, Smart Politics attempts to determine if there is a shortcut in the form of a U.S. Senate ‘bellwether state’ – that is, the state that most frequently elects candidates who form the majority party when the subsequent Congress convenes in January.

A Smart Politics analysis of more than 1,800 U.S. Senate contests since the passage of the 17th Amendment in 1913 finds that the winner of elections in Rhode Island and Nevada have the strongest correlation with partisan control of the chamber with Virginia tallying the longest active such streak at six consecutive cycles.

The Bellwether States

For years, when political observers looked to project a winner in presidential elections they often used the State of Missouri as a guide.

The “Bellwether State” – famous for casting its Electoral College votes for the winning candidate in all but one presidential election from 1904 through 2004, has since ceded its status to Nevada. (Nevada has voted for the winning candidate in 25 of 26 cycles since statehood).

On the U.S. Senate side, five states from three regions of the country have elected Senators helping to form the majority party in the impending Congress at a greater than 70 percent rate: Rhode Island in the East, Nevada and Washington in the West, and Alabama and North Carolina in the South.

The state which comes closest to being called a bellwether across the last century is Rhode Island.

The Ocean State has voted for U.S. Senate candidates from the party that would form the majority in the subsequent Congress in 27 out of 35 contests over the last 100 years, or 77.1 percent of the time.

The state has elected Democrats in each of the last three races, including flipping Republican Lincoln Chafee’s seat in 2006 with nominee Sheldon Whitehouse as the Democrats took back control of the chamber.

From its first popular vote election in 1916 through 1972, Rhode Island elected U.S. Senators forming the majority party in 19 out of 22 contests – only failing to do so in 1922 (with Democratic incumbent Peter Gerry), 1946 (with Democrat J. Howard McGrath), and 1952 (with Democratic incumbent John Pastore).

Since then, the state’s bellwether track record has been a bit more bumpy, electing majority-bound candidates in eight of 13 contests.

Three-term Democratic incumbent Jack Reed will be on the ballot this November in what is considered a safe hold for the party.

Ranking close behind Rhode Island is the State of Nevada.

Even though the Silver State has had a fairly spotty recent history in electing U.S. Senators into the majority, it has nonetheless done so at an impressive 75.7 percent rate over the last century.

Democratic Majority Leader Harry Reid’s 2010 victory was a key, signature win by this measure as many prognosticators had expected him to lose his bid for a fifth term (and control of the chamber for his party) that cycle.

Between 1932 and 1992, however, the Silver State definitely earned bellwether state status in elections to the nation’s upper legislative chamber.

Nevada elected U.S. Senators from the party that would control the chamber during the subsequent Congress in an astounding 22 of 23 cycles, or 95.6 percent of the time.

Across these 60 years, the only time Nevada failed to do so was in 1974, when Republican Paul Laxalt edged Reid by just 624 votes.

During that remarkable stretch, Nevadans voted for Republican nominees five times (1946, 1952, 1974, 1980, 1982) and Democrats 18 times (1932, 1934, 1938, 1940, 1942, 1944, 1950, 1954, 1956, 1958, 1962, 1964, 1968, 1970, 1976, 1986, 1988, 1992).

Nevada will not hold a race for the Senate until 2016, but four of the remaining Top 10 ranking states will.

Three other states have elected majority-bound U.S. Senators at a 70+ percent rate over the last 100 years: Alabama at 73.7 percent (28 of 38 contests), North Carolina at 72.5 percent (29 of 40), and Washington at 71.4 percent (25 of 35).

Prior to the last two cycles in which Republicans Richard Shelby and Jeff Sessions were elected from the minority party, Alabama had voted U.S. Senators into the majority party during 20 of 21 cycles from 1948 through 2004 (with Democrat Howell Heflin’s 1984 victory the lone exception during this 56-year period).

Rounding out the Top 10 are Arkansas at 69.4 percent and Connecticut, Georgia, Missouri, and Ohio at 68.4 percent.

Alabama, Arkansas, North Carolina, and Georgia will all conduct U.S. Senate elections this cycle, with the latter three all high profile races.

The Anti-Bellwether States

At the other end of the spectrum, six states have elected U.S. Senators over the last century that have ended up in the subsequent Congress’ minority party at least more often than not.

Two states – Kansas and Vermont – have truly been anti-Bellwethers, sending senators to D.C. who have been in the majority party at less than half the rate of states like Rhode Island, Nevada, Alabama, and North Carolina.

Kansas is at the bottom – electing Senators in the majority party only 35.1 percent of the time (13 out of 37 contests).

This is largely due to the state being the reddest in the nation when it comes to senatorial elections. The last Democrat to win Kansas was George McGill in 1932 – some 29 cycles ago.

Vermont – which has yet to elect a Democrat to its Class I seat in history – has elected senators into the majority in just 14 of 39 cycles, or 35.9 percent of the time.

Massachusetts is next at 43.2 percent, followed by South Dakota at 47.1 percent, Oregon at 47.4 percent, and Nebraska at 48.6 percent.

Rounding out the Bottom 10 are New Hampshire (50.0 percent), Illinois (51.4 percent), New York (51.4 percent), and North Dakota (51.4 percent).

U.S. Senate ‘Bellwether State’ Rankings, 1913-2012

Rank	State	# Majority	# Minority	Total	% Majority
1	Rhode Island	27	8	35	77.1
2	Nevada	28	9	37	75.7
3	Alabama	28	10	38	73.7
4	North Carolina	29	11	40	72.5
5	Washington	25	10	35	71.4
6	Arkansas	25	11	36	69.4
7	Connecticut	26	12	38	68.4
7	Georgia	26	12	38	68.4
7	Missouri	26	12	38	68.4
7	Ohio	26	12	38	68.4
11	Montana	23	11	34	67.6
12	Florida	24	12	36	66.7
12	Alaska	14	7	21	66.7
14	Louisiana	23	12	35	65.7
14	Oklahoma	23	12	35	65.7
16	Kentucky	26	14	40	65.0
17	South Carolina	23	14	37	62.2
17	West Virginia	23	14	37	62.2
17	Wisconsin	23	14	37	62.2
20	Colorado	22	14	36	61.1
20	Michigan	22	14	36	61.1
20	New Mexico	22	14	36	61.1
23	Pennsylvania	23	15	38	60.5
24	California	22	15	37	59.5
24	Minnesota	22	15	37	59.5
24	Virginia	22	15	37	59.5
27	Delaware	21	15	36	58.3
27	Mississippi	21	15	36	58.3
29	Maryland	20	15	35	57.1
29	Hawaii	12	9	21	57.1
31	Texas	21	16	37	56.8
32	Arizona	19	15	34	55.9
32	Utah	19	15	34	55.9
34	Iowa	20	16	36	55.6
35	Indiana	21	17	38	55.3
35	Tennessee	21	17	38	55.3
35	Wyoming	21	17	38	55.3
38	Maine	19	16	35	54.3
39	Idaho	21	18	39	53.8
40	New Jersey	20	18	38	52.6
41	Illinois	19	18	37	51.4
41	New York	19	18	37	51.4
41	North Dakota	19	18	37	51.4
44	New Hampshire	18	18	36	50.0
45	Nebraska	18	19	37	48.6
46	Oregon	18	20	38	47.4
47	South Dakota	16	18	34	47.1
48	Massachusetts	16	21	37	43.2
49	Vermont	14	25	39	35.9
50	Kansas	13	24	37	35.1
	Total	1,069	737	1,806	59.2

Note: Includes general and special elections. Only winning candidates from a state who share the party label of the impending majority party are counted, even though a few independents and third-party candidates would later join the majority caucus (e.g. Angus King of Maine in 2012). Table compiled by Smart Politics.

Bellwethers in Recent Years

In recent years, as partisan control has switched from the GOP to the Democrats, very few states have elected U.S. Senators for more than a few cycles that correlated to control during both eras.

Virginia has the longest current streak at six cycles dating back to the Election of 1996.

The Old Dominion State elected Republicans John Warner (1996), George Allen (2000), and Warner again (2002) while control of the chamber remained with the GOP and then Democrats Jim Webb (2006), Mark Warner (2008), and Tim Kaine (2012) as it flipped and remained with the Democrats.

The election of Webb over Allen in 2006 by less than 10,000 votes was a crucial victory for the Democrats to win back the chamber for the first time in 12 years.

Senator Warner is seeking a second term in 2012 against likely GOP nominee Ed Gillespie – former Chairman of the Republican Party.

Only five other states have streaks of four consecutive contests.

Minnesota and New Mexico each have done so since 2002 while the streaks for Delaware, New York, and West Virginia began in 2006 (and include special election contests).

Looking a bit more broadly, three other states stand out as recent bellwethers over the last few decades: Ohio, Pennsylvania, and New Hampshire.

Ohio has elected U.S. Senators of the majority party in the subsequent Congress in nine out of 10 cycles since 1986, with Rob Portman’s win in 2010 the only victory by a candidate of the next Congress’ minority party.

Democrats took back and retained party control of the U.S. Senate along with the election of John Glenn (1986, 1992), Howard Metzenbaum (1988), and Sherrod Brown (2006, 2012) while Republicans did the same with victories by Mike DeWine (1994, 2000) and George Voinovich (1998, 2004).

The election of U.S. Senators in Pennsylvania has correlated to control of the Senate in six of the last seven cycles since 1994 (with GOPer Pat Toomey’s 2010 win the only blemish).

New Hampshire voters have sent to Washington majority party victors in five of the last six contests since 1996 (with Republican Kelly Ayotte’s 2010 victory the lone exception during that span).

No other state has been even a somewhat reliable bellwether for which party will control the U.S. Senate over the last two decades.

2014 Battlegrounds

In the 2014 cycle, more than a dozen states have been targeted as either competitive, potentially competitive, or likely to flip this November.

Among these states, North Carolina’s electoral history has the highest correlation to impending control of the chamber, with 72.6 percent of its winners sitting in the majority over the decades.

The Tar Heel State is currently a toss-up between one-term Democratic incumbent Kay Hagan and several GOP challengers, led by State House Speaker Thom Tillis.

Arkansas (69.4 percent), Georgia (68.4 percent), Montana (67.6 percent), and Alaska (66.7 percent) have also elected U.S. Senators into the majority party at least two-thirds of the time.

States to watch in 2014 with the weakest history of electing senators in the majority are South Dakota (47.1 percent of the time), New Hampshire (50.0 percent), and Iowa (55.6 percent).

Here is the bellwether rating over the last 100 years for each of the key states with Senate elections in November:

U.S. Senate Bellwether Ratings for Key States in 2014 Cycle

State	Rating
North Carolina	72.5
Arkansas	69.4
Georgia	68.4
Montana	67.6
Alaska	66.7
Louisiana	65.7
Kentucky	65.0
West Virginia	62.2
Colorado	61.1
Michigan	61.1
Minnesota	59.5
Virginia	59.5
Iowa	55.6
New Hampshire	50.0
South Dakota	47.1

Table compiled by Smart Politics.

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