Why did the Federalist party collapse?

Question

The Federalist Party in the United States was a significant political force during the early years of the United States' history. Wikipedia doesn't really cite reasons why the party declined and eventually ceased to exist - what would you cite as the one main reason for their decline and collapse?

Answer 1

A major factor was the war of 1812. The Federalist party for a long time supported peace with Britain and war with France whereas the Democratic-Republican party had the exact opposite position. Eventually, British behavor towards the US during its war with France caused anti-British and thus anti-Federalist sentiment. Quoting the Wikipedia regarding the first point:

Britain used her navy to prevent American ships from trading with France (with which Britain was at war). The United States, which was a neutral nation, considered this act to be against international law. Britain also armed Indian tribes in the Northwest Territory and encouraged them to attack settlers, even though Britain had ceded this territory to the United States by treaties in 1783 and 1794. Most insulting though was the impressment of seamen as the Royal Navy boarded American ships on the high seas...

...An angry public elected a “war hawk” Congress, led by such luminaries as Henry Clay and John C. Calhoun.

The war start with territorial ambitions on the American side but ended in status quo ante bellum. Nevertheless it was deemed as a great success, a "second war of independence" and a great wave of patriotism surrounded American victories. In particular, General Andrew Jackson became a national hero which helped him becoming a president in 1829.

Especially important in the collapse of the Fedaralist party was the Hartford Convention of 1814-1815. This mostly Federalist convention in New England ended up suggesting some constitutional amendments but was alleged to consider the secession of New England from the Union and a separate peace with Britain. After the war the convention was widely viewed as an act of treason and a black mark on the reputation of the Federalist party.

Answer 2

The Federalist party had the perception of favoring the upper class, and as a result they began to lose support of the general population. The Democratic and Republican parties started focusing on issues that appealed more to the "common man", and as a result began to sway voters away from the Federalist party until it finally ceased to exist.