The appointment was conducted by a panel of local Democratic leaders chaired by Senator Steven Landek, the Committeeman from Lyons Township.
Villanueva was one of five candidates, who included: Carlos Aparicio, Chief of Staff for Cook County Commissioner Jeff Tobolski; John Chojnacki, law enforcement instructor at Calumet College of St. Joseph; Sergio Rodriguez, Mayor of Summit; and Myra Ortiz, Village Trustee in Summit.
During her first term, Villanueva was a leader in pushing for a bill that limit how much public agencies in Illinois could cooperate with U.S. Immigration and Customs Enforcement.
[5] In November 2019, Villaneuva launched a campaign to replace resigning Illinois State Senator Martin Sandoval.
[5] On January 7, 2020, Villaneuva was appointed to become state senator of the 11th district, after Sandoval's resignation amid a corruption probe.