Ebbin decided to give up his seat in the House of Delegates to run for the
Virginia State Senate in 2011, following Patsy Ticer's announcement that she would not seek re-election. He ran in the 30th district, comprising parts of Arlington, Alexandria and Fairfax County; the district leans heavily Democratic. He faced a heated Democratic primary election held on August 23, 2011, with two opponents:
Rob Krupicka, a member of the Alexandria city council, and
Libby Garvey, a member of the Arlington school board. Krupicka, who led in fundraising, was widely considered the favorite but Ebbin prevailed narrowly in what local newspapers called an "upset" and a "shocker". Ebbin took 39% of the vote to Krupicka's 36% and Garvey's 25% – a margin of 335 votes. The 30th district race was the second most expensive primary in the state, with the three Democratic candidates raising a combined $746,000. In the general election, Ebbin faced Republican candidate Tim McGhee and prevailed easily. He took office as a Virginia state senator on January 11, 2012. Ebbin served on five Senate committees: Finance and Appropriations; Commerce and Labor; Privileges & Elections; General Laws and Technology; and the Transportation Committee. He serves on a number of Commissions and interim Committees including the Task Force to Commemorate the Centennial Anniversary of Women's Right to Vote, the Joint Commission on Administrative Rules, the Northern Virginia Transportation Commission, and the Joint Subcommittee to Evaluate Taxation Preferences. He also passed legislation to decriminalize marijuana, allow localities to institute fees on throw away bags, and create a legal avenue for employees to sue their employers for wage theft. In 2021, Ebbin passed legislation legalizing the simple possession of cannabis and was appointed Chair of the General Assembly Cannabis Oversight Commission, which oversees the structuring of the proposed legal market for adult use cannabis in Virginia. During the 2022 legislative session, Ebbin was elected Chair of the Senate Privileges and Elections Committee, becoming the second out LGBT official to serve as a General Assembly Committee Chair. ==2014 Congressional Campaign==