By Jon Frandsen, Senior Editor January 13, 2009 The decision by Sen. George Voinovich, R-Ohio, to retire in 2010 means at least three Republican Senate seats in swing states that already have a Democratic senator, Florida and Missouri as well as Ohio, will be open. That and the already uphill battle faced by the GOP in the chamber (they have to defend 19 seats, the Democrats 17) give Democrats a strong shot at a filibuster-proof majority in the midst of Barack Obama's term.On top of that, GOP Sen. Sam Brownback won't seek reelection either, leaving to run for governor of Kansas, a state that leans Republican but has a Democratic governor and could be won by the right type of Democratic candidate.Of course it is a little silly to be handicapping 2010 when it is impossible to know what the political climate will be like in nearly two years. After all, Democrats will have to defend a seat in Republican leaning Colorado once Sen. Ken Salazar is confirmed as Obama's Interior secretary, and while few Democrats up for reelection in 2010 appear vulnerable right now, that picture could change rapidly if Obama falls flat on his face or economic and security conditions in the country deteriorate. But what's not silly is to consider the immediate ramifications of Republicans faced with the prospect of not just being in the minority, but not even having the threat of a filibuster as leverage with Democrats.That sword of irrelevancy dangling over their heads could influence Republicans as they consider the role they want to play in the next two years. They can fight every proposal they find distasteful tooth and nail, routinely slowing things down and perhaps even stopping some legislation. But that will give Democrats a club in 2010 -- the opportunity to portray Republicans as obstructionists bent on thwarting popular will for their own ideological and partisan ends. It's a script the GOP knows well since it used it to take back the Senate in the middle of President Bush's first term. In response, Democrats would argue that Republicans must be stripped of the power of filibuster because they were standing in the way of progress and prosperity,There's another path congressional Republicans could take: Accept their limited role and try to influence legislation where they can, reserving the filibuster for battles over signature issues important enough for voters to remember and for the party to feel comfortable defending. That would let GOP candidates claim a share of any legislative successes engineered by Obama and the Democratic majority while still drawing distinctions between the parties. It would make issues the focus of a campaign, not their role as obstructionists.Republicans could also put less emphasis on party unity and discipline and more on letting individual lawmakers develop and pursue areas of expertise and concern that play well in their district or home state without fear of retribution from the leadership. That would make it far easier for Republicans in swing states or Democratic states to survive and harder for Democrats to beat them simply because they are Republicans, which is what happened to Gordon Smith of Oregon and John Sununu of New Hampshire. Those steps could also help repair the GOP's image as a party that can campaign but not govern and to begin broadening its appeal beyond the party's base of hardcore conservatives.Being so tantalizingly close to a filibuster-proof majority also could affect Democrats. Counting the two independents who caucus with the Democrats and assuming that Al Franken remains the winner of the Minnesota race and that Democrats hold onto seats up for grabs as senators, they control the Senate 59-41. Since they often would have to pick off just one or two Republicans to kill a filibuster, Democrats will be sorely attempted to craft bills that only need one or two GOP votes.But that's not the type of governance Obama has promised to bring to Washington. He is going to have to work hard with Democrats to develop legislation in such a fashion that it can can draw enough Republican support to be regarded as truly bipartisan. Otherwise Democrats will be as open to charges of partisanship and ideological purity as Republicans have been.