An educator and lobbyist before first running for the legislature in 2004, Kefalas defeated a Republican incumbent to win election to the Colorado House of Representatives as a Democrat in 2006.

[2] Born in Piraeus, Greece,[1] Kefalas earned a bachelor's degree in botany[3] from Colorado State University in 1978 and then joined the Peace Corps in 1979, serving as an agricultural extension worker in El Salvador.

[1] After returning to the United States, he earned a master's degree in teaching, with a secondary science specialization from Fairleigh Dickinson University[3] in 1982 and taught in the Poudre School District.

[7] From 1980 to 1994, Kefalas redirected a portion of his federal income taxes to charitable organizations[8] as a protest against United States military actions in Central America.

[9] Kefalas is married; he and his wife Beth have two sons — Harlan, an active-duty U.S. Army soldier who has served in Iraq, Kosovo, and Afghanistan,[13] and Timothy, the coach of the Colorado State University ultimate frisbee team.

[1][6] Kefalas first ran for the state legislature in 2004, winning the Democratic Party primary by only seven votes over Fort Collins councilman Bill Bertschy after a recount process that lasted for several weeks.

[14] Kefalas lost the general election by fewer than 500 votes to incumbent Republican Bob McCluskey in a race that also included Libertarian Party candidate Jassen Bowman.

[19] Kefalas proposed a bill to explore alternative voting systems,[19] which was defeated in committee,[20] but which led to the creation of an 11-member multi-partisan task force to study related issues.

[21] Another of Kefalas' proposed bills, which would have required the Colorado Department of Revenue to regularly report on tax burdens across individual income groups, was also defeated in committee.

[41] Among Kefalas' top priorities is restoring and expanding Colorado's earned income tax credit,[42] a move which met with resistance from legislative leaders in 2007 due to budget constraints.

[46] Holding office in a closely contested district, Kefalas was expected to be targeted by Colorado Republicans during his 2008 re-election bid,[47] which he formally announced in January 2008.

[50] Former Rep. Bob McCluskey announced his intention to run against Kefalas in February 2008, pitting the two against each other for the third time in as many election cycles[51] and creating a competitive race in what was seen as one of Colorado's "swing" districts.

[60] Kefalas ultimately won a second term with about 59 percent of the popular vote,[61][62] becoming the first Democrat to win re-election in the east Fort Collins district since 1936.

[66][67] The bill was introduced as a proposal to create a 23-member commission to make recommendations as to how to implement a single-payer system, and was reported favorably out of a House committee.