The Milošević years (1991–2000)

Stojmirović joined the Radical Party in 1991, the year of the party's formation, and was a frequent candidate for public office in the 1990s. He sought election to the Yugoslavian federal assembly's Chamber of Citizens in the May 1992 federal election in the single-member constituency of Mladenovac and finished second against Radivoje Jovanović of the Socialist Party of Serbia.^[3]

He subsequently received the eighteenth position on the Radical Party's electoral list for the Belgrade division in the 1992 Serbian parliamentary election and the fourteenth position in the same division in the 1993 parliamentary election.^[4][5] The Radicals won twelve seats in Belgrade in 1992 and seven in 1993; Stojmirović was not selected for its assembly delegation on either occasion.^[6][7] (From 1992 to 2000, Serbia's electoral law stipulated that one-third of parliamentary mandates would be assigned to candidates from successful lists in numerical order, while the remaining two-thirds would be distributed by the sponsoring parties amongst other candidates.^[8] It was common practice for the latter mandates to be awarded out of numerical order. Stojmirović could have been awarded a mandate on either occasion despite his relatively low position, but he was not.)

He received the second position on the Radical Party's list for the Voždovac division in the 1996 Yugoslavian parliamentary election.^[9] The Radicals won only one seat in the division, and he was again not elected.^[10]

For the 1997 Serbian parliamentary election, Stojmirović received the eighth position on the Radical Party's list for the Čukarica division in Belgrade.^[11] The party won four mandates in the division,^[12] and on this occasion he was included in its assembly delegation, serving his first term in parliament.^[13] The election was won by the Socialist Party of Serbia and its allies. The Radicals initially served in opposition, although from 1998 to 2000 the party participated in a coalition government with the Socialists and the Yugoslav Left. After the fall of Slobodan Milošević's administration in October 2000, a new transitional government was established that excluded the Radicals, and the party returned to opposition.

Stojmirović ran in Zvezdara's ninth constituency for the City Assembly of Belgrade in the 2000 Serbian local elections. He lost to Dragan Šutanovac of the Democratic Opposition of Serbia.

After the fall of Milošević (2000–08)

Serbia's electoral system was reformed prior to the 2000 Serbian parliamentary election, with the entire country becoming a single electoral constituency and parliamentary mandates being awarded to listed candidates at the discretion of successful parties, without any specific reference to numerical order.^[14] Stojmirović was included on the Radical Party's list in 2000.^[15] The party won twenty-three seats, and he was not included in its assembly delegation.

He was elected to both the Belgrade city assembly and the Zvezdara municipal assembly in the 2004 Serbian local elections, leading the Radical Party's list in the latter jurisdiction.^[16] He was president (i.e., mayor) of Zvezdara from February to June 2005, in the context of a local alliance with the Democratic Party of Serbia, the Socialists, and other parties. He also sought election as chair of the Assembly of the City of Belgrade in November 2007, although he was not successful.^[17][18]

He was included on the Radical Party's electoral lists in the 2007 and 2008 parliamentary elections, though he was not included in its assembly delegation on either occasion.^[19] He was also included on the Radical Party's list for the Belgrade city assembly and again held the lead position on the party's list for the Zvezdara municipal assembly in the 2008 Serbian local elections, but he did not take a seat at either level.^[20]