As Russia gears up for Duma elections on December 2, the opposition squeeze continues. What’s interesting: Putin’s use of institutional change to entrench a power grab. Term-limited, he cannot legally seek the presidency again. Rather than breaking the law, it seems, Putin plans to keep power by changing it.

Last summer, he secured the elimination of the nominal tier in Duma elections, replacing a non-compensatory mixed system with pure list proportional representation. Coverage emphasized how the change would make it more difficult for small, local parties to win seats.

In the 2003 Duma election, United Russia led in the list tier with 37.6 percent of votes and 120 of 225 seats. Despite an aggregate United Russia plurality in the nominal tier, the majority of these seats was distributed among numerous smaller parties. United Russia’s final seat share was only 49.3 percent.

On October 2, Putin declared his candidacy as prime minister, agreeing to head United Russia’s list in the December election. Polling around 54 percent nationally, United Russia looks poised to win a solid majority. Add to this a 7 percent threshold and the fact that, according to the same poll, the runner-up Communists are polling only 6 percent. “Solid majority” appears an understatement.

What’s more, a new round of stringent ballot access restrictions makes the landscape even worse for Russia’s small opposition factions. New York Times readers will recall a front-page story today on the situation; to get on the ballot, one used to need 10,000 signatures. Now one needs 50,000.

The rule changes look like part of a broader plan to centralize the Russian state. In May 2006, Russia’s last elected governor was arrested “on suspicion of fraud and embezzlement.” For over a year, the president has had the power to appoint regional executives.

Russia’s municipalities now appear to be the last bastion of institutional opposition.