Now that Pennsylvania Senator Arlen Specter has all-but certainly handed Democrats a filibuster-proof majority in the United States Senate, we can finally put aside those increasingly annoying stories speculating about who is "leading" the Republican Party and what "state" the GOP finds itself in. Those questions are largely pointless from a practical standpoint, as is the GOP's political power in Washington at the moment.

That doesn't mean it is all good news for Democrats.

Over the past five months, political watchers, pundits and the Washington press corps have been sidetracked from time to time by the drama that is the GOP's apparent implosion. Were party leaders taking their marching orders from Rush Limbaugh on the stimulus bill and everything else? Would the GOP find itself marginalized by Southern conservatives or broaden the tent, as RNC Chairman Michael Steele suggested, to constituencies as diverse as "urban-suburban hip-hop settings" and "one-armed midgets"?

The more pertinent question was rarely, if ever, asked - why should anyone really care?

Under the circumstances following the 2008 elections, one could make a small but specious case that the GOP retained a modicum of power. Democrats appeared to have come up at least one seat short of gaining the nine Senate seats required to gain a stranglehold on the federal government. They took seven away from Republicans and, after months of legal wrangling, appear to be on the verge of gaining another one in the contested Minnesota race.

Now Specter has apparently given Democrats the magical number 60 in the Senate to add to their 40-seat majority in the House. A popular president with an ambitious agenda now should have the legislative muscle to carry it through Congress.

That's where the bad news comes in for the ruling party. The dirty little not-so-secret surrounding the administration's plans has always been that a handful of Democrats were much more of a threat to its agenda than any Republican opposition.

It isn't conservative Republicans the administration has to fear in pursuing their agenda but rather moderate and conservative Democrats. In the Senate, powerful Democrats like Kent Conrad from North Dakota have sent some powerful messages to the administration on key agenda items like cap-and-trade, deficit spending and farm subsidies. Other items, like health care reform and Big Labor's "card check" push appear to remain in limbo if not injured. And in the House, a group of about 50 blue-dog Democrats can be counted on to make at least a little noise in these big debates.

This is the Democrats' show now in totality. To paraphrase Colin Powell, if they break it, they will own it.

Ironically, Specter may have done more politically for his former party than ever before by simply leaving it. As long as the Pennsylvania moderate was in their caucus, the onus was on the GOP to keep him happy. Now, the burden of mustering those 60 votes belongs solely to the administration and Democratic Party.

Specter, along with a small cadre of GOP moderates like Maine's Olympia Snow and Susan Collins have long been swing votes in the Senate. For President Obama, they have been vital. If they vote with the Democrats - as all three did in the stimulus debate, providing the final margin of passage - the administration could hail the bipartisan accomplishment. If not, they could be attacked as having caved in to Limbaugh-like, right-wing pressures.

In other words, Specter has been one of a very few Republicans who've made it possible for Democrats to gain traction out of nearly any outcome. Without 60 votes, there's always an opposition to blame, always the Republicans to call obstructionists. Now that illusion is shattered. There are no more legitimate GOP bogeymen for Democrats outside their own ranks -- at least for now.

The administration has the kinds of majorities in the House and Senate no party has had for decades. Suddenly, the pressure is on them to manage it completely and that won't be easy. In his press conference Tuesday afternoon, Specter made two things very clear. First, that he had decided that running for re-election as a Republican was a losing proposition. Second, that his famed "independence" would remain a distinguishing characteristic of his Senate career.

Both spell potential trouble for Democrats. They have been given nearly absolute power by a politician who freely acknowledges he's switched parties in order to be re-elected and who all-but threatened to be as much of an ideological roadblock for his new party as he was for his former one. Bottom line -- he's the Democrats' problem now, and not their only one.

The Republican Party will continue to be a political fascination going forward, but one that is more a sideshow than anything else. Assuming, as nearly everyone believes, Al Franken ends up prevailing in his legal battle with Norm Coleman in Minnesota, the GOP will have lost one of their last pieces of ammunition - the Senate filibuster.

Democrats have had a luxury over the past 100 days. They've been able to put at least some of the focus on Republican opposition to much of Obama's agenda, painting them as the "party of no," dredging up phantoms of talk radio hosts run amok and ridiculing the GOP for failing to push forward their own specific agenda items. The focus now shifts solely onto the majority and their own not-so-insignificant intra-party pressures.

In reality, the GOP hasn't had the chance to do much of anything since last November and the fulcrum rested in the hands of a tiny number of senators like Specter. Now he's a Democrat and the party in power is out of an opposition to blame for much of anything, probably at least until 2010.