It's easier to answer the question by how many years have the Republicans controlled both houses since 1950...the answer...only four...and two of those four the majority in the Senate was 51-49, a razor thin and actually Democrat controlled since at least four Republican senators were liberal in voting.
Legislative bodies are difficult to 'control' all the time, but you are asking "For how long have the Democrats controlled Congress?"
In fact, if you are asking by the numbers, the United States House of Representatives (half of Congress) has more Republicans than Democrats at this moment in History.
The United States Senate (the other half of Congress) is narrowly Democratic. And the control of the Senate and of the House has swung back and forth since The Republican Revolution of 1994 mid-term elections which ended 40 years of Democratic majorities in Congress. Not necessarily 'controlling' but at least in numerical superiority.
Well, for the past 2 years, the Democrats have held the majority, and control, in the House. They will now remain in power for atleast 2 more years. The Republicans held the majority for quite a while before that.
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As of 2011, Gallup polling found that 31% of Americans identified as Democrats (tying a 23-year low), 27% as Republicans, and 40% as independents (largest in 60 years). Nevertheless, since more independents leaned to the Republicans, when including the leaners, the democrats and republicans ended up tied at 45 percent (from wikipedia)
It has been controlled by the Democratic Party since 1970 except during 1995 and 1996.
There are about 72 million registered democrats in the U.S.
The GOP controlled the house and senate for first 6 of 8 years. The last 2 were controlled by the Dems.
For two years, the Democrats held both Houses. At mid-term elections of Clinton's first term, the Republicans gained control of, and kept control of, both houses for the remaining six years of Clinton's presidency.
The Democrats controlled both houses of Congress in all the four years that George H. W. Bush was president and for two years when George W. Bush was president.
The Democrats controlled both houses of Congress during the George H.W. Bush years
Well we are a republican form of government controlled by the Democart party. The Democrats have been in charge of congress for the last two years.
It was controlled by Democrats the first 2 years, and by Republicans for the last 6 years.
During much of President Bush's administration, congress was controlled by Republicans. That changed, however, with the 110-111 congress (Jan-04,2007 - Dec-22,2010), at which time, both the house and the senate now had a majority of Democrats. But although Barack Obama had a Democratic congress for the first year and a half of his presidency (Jan 2009 to Nov 2010), that changed in the 2010 midterm elections. Ever since Jan-05, 2011, the 112th congress was divided: it had a majority of Democrats in the Senate and a Republican majority in the House.
Democrats controlled BOTH house from 1955 until 1980 (26 years). From 1981 until 1987 the Republicans controlled the Senate and the Democrats the House. Democrats recaptured both houses in 87 and held them until 95 when the Republicans took both houses and held them until 2005.
democrats held the majority of the seats for many years
The number of Republicans and Democrats in the House changes every 2 years. The current House of Representatives, of the 112th United States Congress, now seats 242 Republicans and 193 Democrats.
Congress has become more evenly split between republicans and democrats.
The length of the presidencies of FDR, Truman, JFK, LBJ, and Carter adds up to about 32 years.