The ODS's widely anticipated victory over the ČSSD in Senate and local elections Oct. 20–21 turned out more like a landslide — averaging out at 36 percent of the vote to 17 percent, according to media — and now the Social Democrats are pinning their survival on forming last-minute coalitions that could take votes away from the ODS.

There's another round of voting in the Senate election set for Oct. 27–

28, with ODS candidates contesting in 26 out of 27 constituencies. The ODS is defending 10 of its 35 seats in the Senate, but is widely expected to gain seats once votes are tallied in this weekend's poll. Some analysts predict the party could end with close to 50 seats in the 81-seat Senate.

President Václav Klaus is thus likely to tap another ODS member to be the country's next prime minister, despite the recent failure of party Chairman Mirek Topolánek to win a confidence vote in Parliament for his ODS-backed Cabinet. After a strong election showing, and, with the ODS's star on the rise, Klaus' next pick could be harder to scuttle.

"The president will have to take into account a massive victory by the ODS," says political analyst Zdeněk Zbořil.

That is likely to strengthen the party's negotiation position in the Chamber of Deputies, which has been in deadlock since June's general election delivered an evenly divided lower house of Parliament.

If there's any surprise so far in the latest elections, it's that the ODS did as well as it did in the Senate poll (it traditionally dominates local elections). A majority in the Senate would eliminate the need for wobbly coalitions and could stand as a buttress for a divided Chamber, analysts say.

But don't look for an immediate end to the Chamber stalemate. "It's too early to draw conclusions," says Vladimíra Dvořáková, a political scientist.

Meanwhile, few small political parties have answered ČSSD Chairman Jiří Paroubek's call to join a coalition against ODS candidates.