When Pennsylvania U.S. Senator Arlen Specter switched from the Republican to the Democratic Party on Tuesday morning, the first question asked was not why he bolted from the GOP, but how his change in party affiliation will impact the Democratic majority’s quest for a filibuster-proof 60 votes on key legislation Barack Obama wishes to push through Congress, such as new energy policy and health care reform.

But what about Specter’s prospects in 2010? Will the veteran lawmaker win his U.S. Senate race in the Keystone State race as a Democrat next year?

If history is any indication, the answer is ‘yes’ – with an asterisk.

Smart Politics analyzed the political fates of the 13 U.S. Senators who switched party allegiances since the introduction of popular vote elections in 1914. All but three Senators returned to office during their next reelection bid under the new party label, and none lost their general election race.

Of the three Senators who did not win a second term, one lost at the primary stage, one opted to retire, and one died in office.

However, the change in party by these 10 Senators resulted in a substantial drop of 52 percent in the margin of victory during their subsequent reelection bids. The average victory margin among these Senators dropped from 36.4 points to 17.5 points under the new party banner, with only two Senators expanding on their margin of victory – Colorado’s Ben Nighthorse Cambpell in 1998 and Minnesota’s Henrik Shipstead in 1940.

But there is an asterisk.

While all this data generally suggests good news for Senator Specter, the Pennsylvanian is the only Senator to switch directly from the GOP to the Democratic Party since popular vote elections were instituted. (In the 1950s Oregon Senator Wayne Morse eventually transformed from a Republican to a Democrat, but not before serving as an independent for three years in the interim).

Moreover, Specter only won reelection in 2004 by a fairly competitive 10.6-point margin – and that was during a pre-Democratic wave election year. Odds are strong there will be some tilt back to the Republican Party nationwide and in Pennsylvania in 2010, after the Democratic landslides of 2006 and 2008. Specter is thus banking on a strong showing in his favor by independents next year, should he win the Democratic nomination.

Change in Party Affiliation in the U.S. Senate, 1914-2009

U.S. Senator
Miles Poindexter
Rep. (1915)
Won (1916)
Robert M. La Follette
Prog. (1924)
Died in office
Robert M. La Follette, Jr.
Prog. (1934)
Won (1934)
George W. Norris
Ind. (1936)
Won (1936)
Henrik Shipstead
Rep. (1940)
Won (1940)
Wayne Morse
Ind. (1952)
Wayne Morse
Dem. (1955)
Won (1956)
Strom Thurmond
Rep. (1964)
Won (1966)
Harry F. Byrd
Ind. (1970)
Won (1970)
Richard Shelby
Rep. (1994)
Won (1998)
Ben Nighthorse Campbell
Rep. (1995)
Won (1998)
Bob Smith
Ind. (1999)
Bob Smith
Rep. (1999)
Lost primary (2002)
Jim Jeffords
Ind. (2001)
Retired (2006)
Joe Lieberman
Ind. (2006)
Won (2006)
Arlen Specter
Dem. (2009)
?? (2010)

Note: Data from U.S. Senate and Clerk of the U.S. House compiled by Smart Politics.

Washington’s Miles Poindexter was a Republican when the state legislature voted him into office in 1910. Poindexter switched to the Progressive Party during the middle of his first term, before returning back to the GOP in 1915. Poindexter was elected into office in 1916 by an 18.3-point margin over Democrat George Turner (55.4 to 37.1 percent).

Wisconsin’s Robert M. La Follette, Jr. switched his party affiliation in 1934 from the Republican Party when he formed the Wisconsin Progressive Party with his brother Philip. La Follete was reelected in 1934 by a plurality 23.6-point margin over Democrat John M. Callahan (47.8 to 24.2 percent) and four other candidates – a sharp drop from his 74.7-point victory in 1928 when he won with 85.6 percent of the vote as a Republican. La Follete’s father, Senator Robert Sr., had similarly switched from the GOP to run as the Progressive nominee for president in 1924, but died in office as Senator in 1925.

Nebraska Senator George Norris served three decades in the Senate, with most of those years as a Republican. In 1936, however, Norris became an independent and was reelected, getting on the ballot by being nominated by petition. Norris won by just 6.0 points that year with 43.8 percent of the vote over Republican Robert G. Simmons. Norris had won by a comfortable 17.1-point margin during the 1930 election, winning 56.8 percent of the vote in his victory over Democrat Gilbert M. Hitchcock.

Minnesota Farmer-Laborite Henrik Shipstead became a Republican during his reelection run of 1940 and is one of only two Senators that have switched parties to increase their margin of victory from the previous election cycle. In 1934, Shipstead won by 20.7 points over Democrat Einar Hoidale, with only a plurality 49.9 percent of the vote. In 1940, Shipstead won by 27.3 points over Farmer-Laborite Elmer A. Benson by a 53.0 to 25.7 percent margin.

Oregon’s Wayne Morse was elected as a Republican in 1944 and 1950 – the latter by a 51.6-point margin over Democrat Howard Latourette, winning 74.8 percent of the vote. Morse became an independent in 1952 and then a Democrat in 1955. Morse prevailed in the 1956 election, but only by 8.4 points over Republican Douglas McKay, 54.2 to 45.8 percent.

South Carolina Senator Strom Thurmond ran unopposed in 1960, winning 100 percent of the vote. In 1964, Thurmond switched to the Republican Party – at the front end of a gradual partisan shift in the South. Thurmond won by 24.4 points in his reelection bid of 1966 over Democrat Bradley Morrah, Jr, winning with 62.2 percent of the vote.

Virginia’s Harry F. Byrd won as a Democrat for his 1st term to the U.S. Senate in 1964, receiving 63.8 percent in a crowded field of five independent candidates and Republican Richard A. May. Byrd defeated May by 44.8 points. Byrd announced his departure from the Democratic Party in 1970, and won 53.5 percent of the vote and reelection as an independent candidate later that year, although by just 22.4 points over Democrat George C. Rawlings – exactly half his 1964 margin of victory.

After the Republican Revolution landslide election of 1994, Alabama Senator Richard Shelby left the Democratic Party in favor of the GOP. Shelby won his third term in 1998 by 26.6 points over Democrat Clayton Suddith, winning with 63.2 percent of the vote. This was a slightly poorer performance than Shelby’s second Senate victory in 1992, when he won 64.8 percent of the vote as a Democrat in his defeat of Republican Richard Sellers by a 31.7-point margin.

One year after Shelby’s defection, Colorado Senator Ben Nighthorse Campbell also switched to the GOP. Campbell, however, increased his margin of victory in winning his 2nd term in 1998 – notching 62.5 percent of the vote in his 27.5-point victory over Democrat Dottie Lamm and five third party candidates. Campbell had won a fairly competitive 9.1-point victory as a Democrat over Republican Terry Considine in 1992, 51.8 to 42.7 percent.

For a few months in 1999 Republican New Hampshire Senator Bob Smith briefly change his affiliation to become an independent, only to reverse course and switch back to the GOP later in the year. The flip-flopping did Smith no favors in the Granite State, as he was defeated in the 2002 Republican primary by John Sununu.

Republican Jim Jeffords became an independent in 2001, and his decision to caucus with the Democrats temporarily gave that party control of the Senate. Jeffords opted not to run for reelection in 2006.

In 2006, Joe Lieberman was defeated in the Democratic primary by Ned Lamont, prompting the Senator to become an independent and run under the Connecticut for Lieberman label in the general election. Lieberman won by 10.0 points over Lamont, with a plurality 49.7 percent of the vote – far shy of the 63.2 percent he received in 2000 as a Democrat, when he defeated Phil Giordano by a 29.0-point margin.

In sum, the incumbency advantage thus seems to insulate Senators when they change political parties mid-stream. The caveat is that most of these Senators, unlike Arlen Specter, had enjoyed extremely large margins of victory during their previous election bids. As such, they were able to hold on and win reelection even though their margin of victory was cut in half on average when running for the first time under the new party label.

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  1. Reaganite Republican Resistance on April 29, 2009 at 1:28 pm

    Everybody knows he did it because he was down 21% in the polls leading-up to the GOP primary for his seat- and Joey Pluggs made a deal with him- he already admitted as-such. The sad truth is that this hack has spent three decades in the Senate, while accomplishing little.

    And Barack and him have a lot in common- as unprincipled political opportunists. I’m sure they’ll get along just great.

    Actually, I would vote for PHIL Spector over Arlen- seems like a more stable and trustworthy individual, lol.

    Just a little over a month ago, the Senator said in an interview that he wouldn’t switch parties due to the importance of checks and balances.

    And back in 2001, Sen. Arlen Specter, then a Republican, proposed a rule forbidding party switches… her was upset when Vt Sen. Jim Jeffords’ left the GOP to become an independent.

    Who knows what the truth is with this guy, you’ll never get it from him.

    With all due respect, Senator- don’t let the door hit your butt on the way out. Nobody on our side’s going to miss you.


  2. Steve Titterud on April 29, 2009 at 2:02 pm

    An interesting question about Sen. Specter’s switch is what happens to campaign contributions made in the assumption he was a Republican?

    His statement included this: “Upon request, I will return campaign contributions contributed during this cycle.”

    The FEC data shows that his receipts for the 2009-2010 election cycle of $1,277,259 – reduced by his disbursements of $352,225 – leaves him with cash on hand of $6,735,915 – not bad!

    But his cash on hand BEFORE “this cycle” was $5,810,882.

    I am wondering just how much he will be asked to refund by contributors? And whether his statement means what it seems to say – he’ll only refund from donations in the $1,277,259 recently collected, NOT from the prior $5 million?

    If I was a loyal Republican giving all along, I’d want it ALL back, not just the most recent contributions! Of course, a good deal of money was given by industry groups, who might not think a change of party alone would affect their interests – e.g., lawyers, as a group, are one of his big sources.

  3. Atif Gulab on May 12, 2010 at 2:19 pm

    Hi. I think that U.S. Senator Arlen Specter is a better choice for Pennsylvania in 2010 than Joe Sestak!

  4. Nikoli Orr on July 2, 2019 at 10:16 pm

    1. VA: The otherwise meticulous “Dr” inexplicably fused (mangled?) the 2 Byrds: the elder Byrd won his final election in 1964 against R A May. Due to precipitously declining health, he resigned from the body in 1965, triggering a 1966 election (held concurrently with the Class 2 standing-election) which was won by his son, against L M Traylor. The younger Byrd would formally leave the party in 1970 over the so-called loyalty oath of the national party (“…a free man than a captive senator…”), but continued to be party of the Democratic Caucus, even while regularly voting with the Rs on many issues, particularly regarding national defence and federal taxation.
    2. Though they are similar cases of intraparty losses, the Smith 2002 and Specter 2010 cases are quite contrastive, in that whereas the R-held WH hierarchy in 2001-02 succeeded in maneuvering to oust Smith by backing J E Sununu (both he and “W” are scions of prominent politicians), the D-held WH hierarchy in 2009-10 failed in making Specter become the nominee of his new/old party by dissuading then-Representative Joe Sestak from challenging him. Incidentally, “Joe from Delco” recently became the second Pennsylvanian – by residence or birth – to seek the presidency for the 2020 election. It remains to be seen if he succeeds in qualifying for the 2-part CNN debate at month’s end (likely not).

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