With the donkeys on the right and the elephants on the left, these sculptures are a bit out of place symbolically.

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When the Democratic Party gathers for its 2008 convention in Denver, Colo., a donkey named Mordecai will give new meaning to the term "political animal." Mordecai is slated to be the first official live mascot in the history of the Democratic Party. The "official 'asscot," as his owner Curtis Imrie has called him, won't deliver an address to the party like Barack Obama or Hillary Clinton will. But Democrats hope his presence in the Mile High City will provide a light-hearted moment or two at the Democratic National Convention (DNC).

There's no word on whether the Republican Party will provide a live counterpart of its animal emblem, the elephant, for its September convention in Minneapolis, Minn. But Mordecai's presence at the DNC raises a sensible question. Just where did these symbols come from? Why do the Democrats choose to affiliate themselves with an oft-ridiculed member of the horse family? And how did the Republicans, the party of social and fiscal conservatism, come to be represented by an ivory-tusked pachyderm?

The origins of these political images lie in the mind of a German-born political cartoonist named Thomas Nast, whose drawings also helped create modern images of Uncle Sam and Santa Claus. Nast moved to New York City when he was six years old and displayed artistic ability at an early age. Because he grew up in New York's thriving society, he worked his political and social knowledge into his artwork.

Nast joined the staff of Harper's Weekly in 1862. By the time he left in 1886, he had not only stamped the elephant and donkey as political party symbols, he'd also become one of the most influential cartoonists in American history. By the time he used the donkey as a Democratic Party symbol, Nast was already a household name. He had ascended to fame with cartoons that depicted the battlefield horrors of the Civil War and helped bring down the Boss Tweed ring, a group of corrupt New York politicians. Read on to learn how Nast's fame led to today's famous symbols.