Grolier's Interactive Encyclopedia:
"The framers of the U.S. CONSTITUTION had hoped to avoid the factionalism of political parties and wrote no role for them into the Constitution. Nevertheless, party divisions began during the administration of the first president, George Washington. The Federalists coalesced around John Adams and the Democratic-Republicans around Thomas Jefferson. The Jeffersonians became the Democratic party, and the Federalists were succeeded by the National Republicans in the 1820s and then by the Whig in the 1830s. The Whigs, in turn, were replaced by the Republican Party in the 1850s. Since then, the Democratic and the Republican party have been the two major parties."
If you hold the writers of this piece to tight grammatical standards, the comma in the fourth sentence is critical to their error. Grammatically-speaking, "The Jeffersonians became the Democratic party" is not connected to the phrase "in the 1820s" as is the clause "and the Federalists were succeeded by the National Republicans." Therefore, this text suggests that only the Federalists coalesced into a party in the 1820s, where actually both parties did not exist until Martin Van Buren's presidency. Yes, the "Federalists," a philosophical movement, "coalesced around John Adams" and "the Democratic-Republicans," another philosophical movement, coalesced "around Thomas Jefferson."
But these movements were just that -- movements. And the Founders actually despised the concept of being held to some common belief system, much less the discipline of a party that would hold them to that system.
And by the way, the reason the Founders, "wrote no role for them (parties) into the Constitution" was they didn't want there to be role a for them. They knew they couldn't stop them (except by the sheer weight of their personalities in the body politic) because, as Madison wrote in Federalist #10, extinguishing them constitutionally would be extinguishing free speech and assembly. But what is often misrepresented as their tacit approval of parties is simply their acknowledgement that, under this constitution, parties would be inclined to emerge, persist, and try to grab power. They disapproved of these eventualities and spoke vigorously against them.
More on Federalist #10 at length later on ...