Ukraine's (search) two presidential candidates mapped out campaign strategies with less than three weeks remaining before the repeat of last month's fraud-marred election runoff, and opposition protesters lifted their two-week siege of the Cabinet headquarters.

The dismantling of barricades near the Stalin-era gray Cabinet building Thursday came after opposition leader Viktor Yushchenko (search) urged his supporters to focus on campaigning for his Dec. 26 rematch with Kremlin-backed Prime Minister Viktor Yanukovych (search).

"This is a sad and happy day at the same time," said Oleksiy, a protester who gave only his first name. "We endured more than two weeks and now we are leaving, but we are leaving as winners."

Tensions in the country's political crisis have abated with the parliament's adoption Wednesday of electoral changes aimed at ensuring a fair ballot in the presidential revote.

A blockade near the president's office remained in place, but Roman Zvarych, a member of Yushchenko's campaign staff, said he believed it, too would be removed.

While demonstrators who had maintained a round-the-clock vigil in freezing temperatures near the Cabinet building melted away, thousands of others remained in tent camps near Kiev's main Independence Square.

Yushchenko said the peaceful 17-day protests, dubbed the "Orange Revolution," had achieved their goals of canceling Yanukovych's fraud-tainted victory in the presidential runoff and pressing home legal changes to keep the rerun vote from being rigged.

Wednesday's surprise parliamentary vote endorsed a compromise package that included electoral reform in exchange for handing over some presidential powers to parliament. Outgoing President Leonid Kuchma long has pushed for the changes in a bid to boost the influence of his allies in parliament.

Parliament also reshuffled the Central Election Commission, ousting its chief. Yanukovych's campaign chief, Taras Chornovil, said his camp now doesn't have a single member in the commission.

Chornovil rejected claims by Yushchenko's supporters that Yanukovych could try to derail the vote.

"They cried thief because it was them who stole," Chornovil said. "It was our victory that has been stolen, not Yushchenko's."

The Supreme Court's annulment of Yanukovych's victory also dealt a heavy blow to Russia, which has staunchly backed the prime minister, fearing that Western-leaning Yushchenko would lead Ukraine away from the Kremlin's orbit.

Kuchma also fired Prosecutor General Hennady Vasylyev on Thursday. Yushchenko's supporters had accused Vasylyev of covering up election fraud.

President Bush on Thursday pressed for strong international support for free and fair voting. He thanked Lithuanian President Valdas Adamkus and Polish President Aleksander Kwasniewski for their mediation in the crisis.

The United States is sending 100 observers — part of a 960-member Organization for Security and Cooperation in Europe team — and spending $3 million toward election monitoring.