Story highlights Wednesday marked one of the busier protest days on Capitol Hill

Two-hundred to 300 people attempting to target all 52 offices of Republican senators

(CNN) The chants of vocal activists echoed through the hallways of Senate office buildings Wednesday, as hundreds staged sit-ins to protest the Republican health care plan that's already on shaky ground.

Clashing with the shouting was the sound of two-way radios from a larger-than-normal police presence to arrest those refusing to heed warnings to stop.

Such protests have become routine on Capitol Hill this summer, but Wednesday marked one of the busier protest days, with 200 to 300 people attempting to target all 52 offices of Republican senators. US Capitol Hill Police told CNN that 155 demonstrators had been arrested Wednesday.

Using the "mic check" approach, groups that ranged from just a few people to a few dozen would walk into offices until they were kicked out. Those willing to risk arrest would then sit on the floor in the hallway and continue to chant their concerns about the bill.

"Please Sen. Toomey! Please don't kill me!" they yelled outside the office of Republican Sen. Pat Toomey of Pennsylvania. "Shame! Shame! Shame!"

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