It would depend on which country you are referring to.
The dominant political party in Canada during the last century was the Liberal Party.
The Longest Cocktail Party was created in 1973.
•During the last half-century, the Democrats have been known as the party of the working class and of racial and ethnic minorities. •During the last half-century, the Republicans have been known as the party of business and known for having an ethic of self-reliance.
The Prime Minister who served the longest in the 20th century was Sir Robert Walpole, who held the office from 1721 to 1742. However, if considering only the 20th century, the longest-serving Prime Minister was Margaret Thatcher, who was in office from 1979 to 1990, serving for over 11 years. Her tenure significantly impacted British politics and the Conservative Party.
The Democrat Party and the Republican Party are the oldest parties in the USA. The Republican Party was formed in the early part of the 19th century & the Democrat Party has its roots well before the formation of the Republicans.
Liberal Party has been around the longest in Canada!
"the common man"
Democrats
he was a polition for the dempcratic party in tammany hall
Republican Party
The Socialist Party of Canada was formed in 1931.
The Whig Party was a political party that was active in the U.S. during the early 19th century. In general, it tended to favor a strong federal role in both moral and economic issues.