Why did some people support the know nothing party?

The Know-Nothing party (aka the Whigs) formed because they didn't like Jackson or his policies.

They formed after the Hartford convention (after which, the Federalist party fell apart).

The Whigs wanted the opposite of the Jacksonian Democrats at this time. They wanted: More gov't support for the economy, a 2nd Bank of the United States (which Jackson despised), and overall more gov't improvement and involvement. Aka, what Jackson did not want.

But after their main reason for forming (opposition towards Jackson), the Whigs were less unified.