The big one, obviously, is Specter vs. Sestak, but there’s a lot on the menu. In Arkansas, Blanche Lincoln needs 50 percent to avoid a runoff with the nutroots candidate; in Kentucky, the Republican base is poised not only to nominate one of the Paul boys for Senate but to do it in a landslide(!); and in Pennsylvania, as an undercard to the main event, Tim Burns could give the DNC a full-on panic attack by stealing Murtha’s seat in the special election. That’s actually the most important race of the night, as a Republican win will drive a thousand stories tomorrow about how November is suddenly looking less like an “anti-incumbent” election than an “anti-Democratic” one. A scene on the ground from this morning featuring Democratic candidate Mark Critz:

“I don’t want to interrupt you, I just wanted to say, ‘Hi, I’m running for Congress,’ ” he told two men in trucker hats and work shirts, who took his hand politely. Both Democrats, one acknowledged later he’d be voting for [Republican Tim] Burns and the other said he was undecided because of his displeasure with the Democrats’ support of the health-care overhaul.

At a nearby table, Richard Gray, 58, a machine operator, said he was a registered Democrat but would be voting for Burns because of his outrage over the health-care bill, which he believes was passed against the wishes of the people. “I’m fed up with the Democrats. It’s like they know what’s better for us than we do,” he said.

Politico’s got you covered if you’re looking to follow returns. With 13 percent of the precincts in Kentucky reporting, Rand Paul already leads by … 18 points. The polls in Arkansas close at 8:30 and in Pennsylvania at 8; stand by for updates, needless to say. To get you motivated for the results, do note that Benedict Arlen ended his primary campaign this morning by observing, “Beating the tea party gang is more important than who does the beating.” As much as I’d like to imagine him crashing and burning tonight, I think he’s actually going to squeak through. Heart-achey exit prediction: Specter 51, Sestak 49.

Update: That was fast.

Political novice Rand Paul rode support from tea party activists to victory in Kentucky’s Republican Senate primary Tuesday night, delivering a jolt to the GOP establishment and providing fresh evidence of widespread voter discontent in a turbulent midterm election season.

Paul had 59 percent of the vote—with returns counted from 29 percent of the precincts—to 37 percent for Secretary of State Trey Grayson, who had been recruited to run by the state’s dominant Republican, U.S. Senate Minority Leader Mitch McConnell.

So there’s your “tea party” storyline tomorrow morning, although I’m not sure it’s one many of the HA faithful wanted. It’s cool to think that Alex Jones will now have a pipeline to the Senate too instead of just the House, huh?