Spokeswoman Candace Martin said kids most likely are the culprits. She said she does not believe the vandalism was politically motivated in any way.
Vandals have hit Democratic Party headquarters with bb pellets six times in the past six months, Martin said. Crews installed the new windows on Monday.
Even though no one was injured, the incident seems to underscore safety concerns.
Both political parties, within blocks of each other in the Capitol District, ramped up their security after a gunman in August 2008 barged into Democratic Party headquarters, shooting and killing Chairman Bill Gwatney.
Republican and Democratic headquarters installed cameras, emergency buttons and controlled access doors with thick glass.
Little Rock police says they have not received any reports of politically-motivated threats or threats of violence against the Republican and Democratic Parties.