They are demanding that authorities reverse a decision to bar the main opposition challengers from running -- a decision that leaves the sole pro-government candidate as the favorite.
Meanwhile, some 500 people in the southern town of Jalalabat are protesting outside the local administration building, where a decision on another opposition politician's candidacy is expected soon.
That politician is former Prime Minister Kurmanbek Bakiev, currently the head of the Kyrgyzstan People's Movement electoral bloc. Bakiyev has already said he will be a candidate in presidential elections later this year.
Other, similar, protests are also going on in the Tong and Tiup districts of Ysykkul region.
(RFE/RL's Kyrgyz Service)
Protesters Rally For Kyrgyz Newspaper