Continued from page 1

Police detained about 300 protesters in Moscow on Monday and 120 participants in a similar rally in St. Petersburg. Two of the Moscow rally’s leaders, Ilya Yashin and Alexei Navalny, were sentenced to 15 days in jail Tuesday.

Security forces already had been beefed up in the capital ahead of the election. Moscow police said 51,500 Interior Ministry forces were involved, all part of increased security for the election period.

Mr. Putin’s comments Tuesday appeared to aim at saving face and discouraging the opposition from seeing United Russia as vulnerable.

“Yes, there were losses, but they were inevitable,” Putin said at a meeting of party supporters. “They are inevitable for any political force, particularly for the one which has been carrying the burden of responsibility for the situation in the country.”

Mr. Putin also rejected the popular characterization of United Russia as “the party of crooks and thieves,” saying corruption was a widespread problem not limited to a single party.

“They say that the ruling party is associated with theft, with corruption, but it’s a cliche related not to a certain political force, it’s a cliche related to power,” he said during a meeting with provincial officials.

“What’s important, however, is how the ruling government is fighting these negative things,” he said.

Mrs. Clinton criticized the Russian vote for a second straight day, saying Tuesday that “Russian voters deserve a full investigation of electoral fraud and manipulation.”

Konstantin Kosachev, a senior United Russia member, described Mrs. Clinton’s statement as “one of the darkest pages in the Russian-U.S. relations” and warned Washington against supporting the opposition.

Russia’s only independent election monitoring group, Golos, which is funded by U.S. and European grants, came under heavy official pressure ahead of Sunday’s vote after Mr. Putin likened Russian recipients of foreign support to Judas. Golos’ website was incapacitated by hackers on election day, and its director, Lilya Shibanova, and her deputy had their cellphone numbers and email and social media accounts hacked.

The Russian election even drew criticism from one of Mr. Putin’s predecessors.

“There is no real democracy here, and there won’t be any if the government is afraid of the people,” former Soviet leader Mikhail Gorbachev said on Ekho Moskvy radio.

Vladimir Isachenkov and Jim Heintz contributed to this report.