Republican Rand Paul, Democrat Jack Conway have early lead in Kentucky primaries

Courtesy of the Commonwealth of Kentucky, we now have the first results from today's multi-state primary elections spree, which features several noteworthy (and unusually fierce) intraparty battles for U.S. Senate.

Early returns from the Bluegrass State suggest decisive victories for Republican Rand Paul and Democrat Jack Conway. Paul's victory, while not unanticipated, is nevertheless a stinging rebuke of the Republican establishment, which had lined up behind Mitch McConnell's man, Trey Grayson. Paul, who is the third child of presidential also-ran Ron Paul, is in many respects a Grover Norquist clone much like Tim Eyman or Bill Sizemore; he has chaired an anti-public services organization called Kentucky Taxpayers United since 2004.

However, Paul is a libertarian, so he has some progressive positions. For instance, he has previously spoken out against the Patriot Act, the Wall Street bailout, and the occupation of Iraq. That's not to say he would be a progressive senator, but he wouldn't be Mitch McConnell's lapdog either.

Meanwhile, Democratic voters appear to have chosen Attorney General Jack Conway to be their standard-bearer, instead of Lieutenant Governor Daniel Mongiardo. Conway previously ran unsuccessfully for the House of Representatives in 2002; he narrowly lost to Republican Anne Northrup, who was herself unseated by Democrat John Yarmuth in 2006.

So it looks like it'll be Conway vs. Paul this fall. The winner becomes the next Senator from Kentucky, succeeding crazy old Jim Bunning, who has become notorious for holding up the Senate's business by abusing the chamber's rules.

UPDATE: As of 5:30 PM Pacific Time, results were:

Republican primary for U.S. Senate
Trey Grayson: 34.45% (45,602 votes)
Bill Johnson: 1.42% (1,877 votes)
Gurley L. Martin: 0.66% (879 votes)
Rand Paul: 61.44% (81,343 votes)
Jon J. Scribner: 0.61% (809 votes)
John Stephenson 1.42% (1,875 votes)

Most of the networks and major Kentucky newspapers have called the race for Rand Paul; he has almost twice the support Grayson is getting.

Democratic primary for U.S. Senate
James Buckmaster: 2.85% (6,466 votes)
Jack Conway: 52.60% (119,319 votes)
Daniel Mongiardo: 35.29% (80,044 votes)
Darlene Price: 5.33% (12,083 votes)
Maurice M. Sweeney: 3.93% (8,918 votes)

SECOND UPDATE: The Democratic primary is being called for Conway, who many activists consider to be the strongest of the Democratic candidates. Conway held on despite losing most of the padding in his lead as the evening wore on.