<P> Democrats regained control of Congress in the 1844 elections, as well, thanks to the huge support of the annexation of Texas, as the 29th United States Congress, but the Whigs were back in control of both houses in 1846, thanks in part to the opposition of the Mexican - American War . The Democrats were able to regain control of Congress in 1848, thanks in part to the U.S. winning the Mexican - American War . The Democrats now had complete control over the 31st United States Congress, despite the break between the anti-slavery (Free Soil Party) and pro slavery Democrats; because of this break, the Democrats would not maintain the U.S. presidency, and Whig Party member Zachary Taylor was elected the 12th President of the United States in the 1848 U.S. presidential election . In 1852, the divide between the pro-slavery southern Wings (who threw their support to Democratic candidate Franklin Pierce and broke with Henry Clay over the Compromise of 1850) and the anti-slavery Northern (who stood behind Clay's compromise and supported the party's nominee Winfield Scott) would also help give the Democrats not only control both houses of Congress, but also the US Presidency as well . In the 1854 elections, the Kansas - Nebraska Act, sponsored by Senator Stephen Douglas, was put against vehement opposition . The opposition to this act led to the formation of the new Republican party . In early 1856, the Know Nothing Party assembled nativists and former Whigs but the Democrats regained control over Congress . During this time the Know Nothing Party and Republican Party united and together, elected Know Nothing Congressman Nathaniel Prentice Banks, as to serve as the Speaker of the House of Representatives for the remaining years of the 34th United States Congress . </P> <P> Through the 35th United States Congress, the Democrats regained control of both houses in Congress; this thanks in part to the division of the Know - Nothing Party and the Republican Party during the 1856 U.S. presidential election . The Know Nothings soon collapsed, and in the North were absorbed by the Republicans, who dominated most states and took control of the U.S. House of Representatives in the 1858 elections, as abolitionist Know Nothings joined the Republican Party after the controversial Dred Scott ruling occurred in 1857 . In 1860, Abraham Lincoln led the Republicans to a victory based entirely in the anti-slavery North, and the Republican Party now took full control of Congress . </P> <P> Congress played a major role in the American Civil War, as the Republicans were in control of both chambers; after the war ended in 1865, Reconstruction was controlled by President Andrew Johnson, who broke with the Radical Republicans (led by Congressman Thaddeus Stevens and Senator Charles Sumner .) After the elections of 1866 the Radicals came to power, impeached (but did not convict) President Johnson, and controlled Reconstruction policy . The Radical hold was broken by the Democratic landslide victories in the election of 1874, and Democrats regained control of the US House of Representatives, this was thanks in part to the Long Depression started by the Panic of 1873 . The Democrats would continue to dominate the US House of Representatives, and even gained control of the US Senate in the 1878 US Senate election as the depression worsened . </P> <P> The Gilded Age (1877--1901) was marked by Republican dominance of Congress--and the Presidency--except in the early years, and some of the mid-years of the Gilded Age -, despite the Democratic lock on the Solid South . The Republican Party, however, would regain control over the US House of Representatives in the 1880 election, as support for the Republican Party's tariff spread among the general public; the Panic of 1873 had also ended for the US in 1879, with the start of the vast immigration into the US that lasted until 1930 . State legislatures continued to elect senators, which meant that the most powerful politicians in the state vied for control of the legislature in order to win election to the Senate . The Democrats, however, retained control of the United States Senate in the 1880 US Senate election, as Virginia's Readjuster Party member William Mahone and Illinois' Independent Party member David Davis were both elected to the US Senate . Both men chose to caucus with the Democrats, thus giving the Democratic Party a 39--37 control of the Senate during the 47th United States Congress . </P>

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