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Republican expansion -

In the 1860s, Republicans controlled northern states, focusing on national expansion, encouraging westward settlement, funding railroads, and promoting state universities, while becoming increasingly opposed to slavery.

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Democratic agrarian ideals -

Democrats favored Thomas Jefferson's agrarian vision, viewing a strong central government as a threat to individual liberty, and most southern Democrats defended slavery as essential to their economy and way of life.

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Republicans push for civil rights -

After the Civil War, Republicans passed the Reconstruction Amendments and civil rights legislation to protect Black Americans, securing their support. However, fierce opposition from southern Democrats limited the long-term success of these reforms.

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Democrats' resistance to civil rights -

Following the war, most Democrats, especially in the South, opposed Republican-led Reconstruction policies that aimed to extend rights and protections to formerly enslaved Black Americans.

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The end of Reconstruction -

The Compromise of 1877 ended Reconstruction, leaving Southern Democrats in control, allowing them to enforce oppressive policies against Black citizens. 

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Republican industrial shift -

By the 1870s, northern industrialists who had grown rich during the Civil War began to dominate the Republican Party, gradually shifting the party's focus from civil rights to business interests.

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The Solid South -

After Reconstruction, the "Solid South" emerged, where the southern states consistently voted Democratic for over 40 years. White southerners supported the party's resistance to civil rights reforms for Black Americans.

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Republican laissez-faire economics -

In the 1920s, Republicans embraced laissez-faire economics, favoring minimal government intervention, which benefitted big business but proved disastrous when the Great Depression hit in 1929.

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Herbert Hoover (1874–1964) -

Republican President Herbert Hoover's refusal to intervene in the economy during the Great Depression led to widespread criticism.

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New Deal reforms -

Democratic President Franklin D. Roosevelt won the 1932 election by promising government intervention and relief programs during the Great Depression, shifting the Democratic Party’s focus toward social welfare.

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New Deal's impact on party ideologies -

The New Deal redefined Democrats as the party of big government and social programs, while Republicans opposed this expansion, arguing that it violated federalist principles. Pictured is a cartoon satire of the New Deal.

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Republican opposition to the New Deal -

In the 1936 election, Republican candidate Alf Landon opposed the New Deal, which solidified the Republicans' small-government platform.

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Civil rights movement -

By the 1950s, the civil rights movement challenged both parties. Southern Democrats and Republicans resisted, while northern counterparts pushed for change.

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Civil Rights Act of 1964 -

Democratic President Lyndon B. Johnson signed the Civil Rights Act into law in 1964. He is seen here shaking hands with Martin Luther King. 

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Democrats become advocates for civil rights -

The Democratic Party's leadership in civil rights legislation in the 1960s reversed its previous opposition, making it the party of social justice and equality for minority groups.

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Goldwater's opposition to Civil Rights Act -

Republican presidential candidate Barry Goldwater opposed the Civil Rights Act of 1964, claiming it expanded federal power dangerously. This stance drove many Black voters from the Republican Party to the Democratic Party.

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Black voters shift to Democrats -

Historically aligned with Republicans, Black voters increasingly supported Democrats by the 1960s, as the Democratic Party emerged as the advocate for civil rights and social justice.

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Southern Democrats resist change -

White southern Democrats resisted the Democratic Party's embrace of civil rights and social reforms, growing disillusioned with the party's direction under Johnson and other liberal leaders.

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The southern strategy -

As southern Democrats opposed civil rights reforms, Republicans began appealing to disaffected white southerners, marking the beginning of the South's gradual shift toward the Republican Party.

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Rise of social issues -

In the late '60s and '70s, some democrats pushed reforms on issues like abortion and school prayer. White southern voters grew increasingly resentful of government intervention, which accelerated their shift to the Republican Party.

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Republican appeal in the south -

By the '70s and '80s, the Republican Party gained substantial support in the South, appealing to conservative voters who rejected the Democratic Party's progressive reforms.

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The Reagan era -

Republican President Ronald Reagan championed conservative values, promoting limited government, deregulation, and a free-market economy, further solidifying new Republican stances. 

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Republican conservatism solidified -

By the '80s, the Republican Party had solidified its conservative platform, emphasizing limited government, traditional values, and economic deregulation.

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Democratic focus on social welfare -

While Republicans embraced conservatism, the Democratic Party strengthened its focus on social justice, civil rights, and government intervention to address economic inequality.

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Republican shift to business-friendly policies -

With the rise of conservatism in the '80s, Republicans aligned closely with business interests, promoting policies that favored deregulation and minimal government interference in the economy.

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The Solid South turns Republican -

The political realignment of the South was complete by the '80s, with white southern voters abandoning the Democratic Party for the Republicans. This reshaped the political landscape of the region.

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Party ideological reversal -

By the late 20th century, the Republican Party, once the champion of federal power, had become the party of limited government, while Democrats embraced government intervention for social justice.

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Modern political landscape -

The modern political landscape reflects the ideological reversal of the two major parties, with Republicans advocating for conservatism and Democrats championing progressive and liberal policies.

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Ongoing divides -

Today, the Republican and Democratic parties maintain clear ideological divisions, shaped by their historical transformations.

Sources: (Live Science) (Student of History) (Stanford Report) 

See also: Republicans who have endorsed Harris and spoken out against Trump

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