Welcome to Congress in the echo-chamber age, where outside influencers have an increasing sway on how Members shape their agenda.

At a time when Rush Limbaugh reaches as many people as vote in Florida and California combined, and when Jon Stewart can draw several hundred thousand people to the nation’s capital, these outsized personalities based far outside the Beltway have become as much a part of Washington’s political ecosystem as the lawmakers themselves.

This phenomenon was most prominent during the long health care debate but has been seen again vividly in the weeks following the Tucson, Ariz., shootings, during the Republican transfer of power and as President Barack Obama prepares his budget.

With Members taking cues from the echo chamber as well as their party leadership, it’s changed the way business gets done. Limbaugh and Fox News hosts Glenn Beck and Sean Hannity can mobilize more voters than any press release or floor speech, so Members find themselves needing to be responsive or face their wrath.

A Republican strategist and former top Republican National Committee aide told Roll Call that Members have one of two reactions when constituents start a message with “I just heard on Rush today …” — “joy and panic.”

Limbaugh has more than 20 million listeners, and most Members couldn’t dream of their message being so widely spread back home, the GOP strategist said.

Read More: By Christina Bellantoni, Roll Call

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