What party did progressives form or stay with?

Progressives primarily aligned with the Progressive Party, which emerged in the early 20th century as a response to the perceived shortcomings of both the Democratic and Republican parties. The most notable iteration of this party was during the 1912 presidential election, when former President Theodore Roosevelt ran as its candidate. Some progressives continued to work within the Democratic Party, especially during the New Deal era under Franklin D. Roosevelt, advocating for reforms that aligned with their ideals.