BRET BAIER, "SPECIAL REPORT" HOST: OK, it's a big night - primary day in Arkansas, Pennsylvania, Kentucky, and Oregon. We have all the races covered, and it's a lot going on because you can see a lot of stuff happening that perhaps could have an effect in the midterm elections.

First of all in Pennsylvania, we have the Senate race there. Senator Arlen Specter trying to hold off a challenge from Representative Joe Sestak. That is a tight race and where we start. Let's bring in our panel, Steve Hayes, senior writer for The Weekly Standard, A.B. Stoddard, associate editor of The Hill, and syndicated columnist Charles Krauthammer. Steve, let's start in Pennsylvania. Heading in, it was very tight. Now there is some talk about turnout in Pennsylvania. Polls don't close until 8:00 p.m. It's raining there. What about this race in the final days?

STEVE HAYES, SENIOR WRITER, THE WEEKLY STANDARD: Certainly the momentum in the last week to ten days has been with Joe Sestak. And you had Ed Rendell, governor of Pennsylvania, who's been a stalwart supporter of Arlen Specter despite the party switch, Rendell representing sort of the establishment in this race, saying if it's raining in Pennsylvania, that's not good for Specter.

Well, it's been raining in Pennsylvania, and its been raining there almost all day. I think most people at this point expect Sestak to win. What's going to be interesting is to see the White House spin on this if he does in fact beat Arlen Specter. The White House backed Specter early and said President Obama would be giving his full support. If Sestak wins at this point, it will be hard for the White House to try to explain why yet again in what is becoming a pattern, the White House-backed candidate lost. But the White House -

BAIER: Vice President Biden was in the area last night giving a commencement address at Penn. President Obama was in the area and flew basically around Pennsylvania today. They've kept arm's length.

HAYES: Yeah, they have kept their distance. There has been heated discussion over the past couple of days as to whether the president would sort of make a last trip to really try to rally the troops as it were for Arlen Specter, and he opted not do that.

I think what's going to be interesting is to see how this is played. I think we already saw a preview of that in a Washington Post article today in which the writer argued in effect that a Sestak win is actually a good thing for President Obama and it could signal that the president has the left bank energized and there will be voter intensity on the left that maybe people didn't anticipate.

That strikes me as overly-optimistic, to be charitable. This was somebody, Specter is somebody who the president said he'd campaign for, and he did campaign for and backed him from the beginning. Just because he doesn't make a last-minute trip there doesn't mean he can disown his support.

BAIER: Another important race, A.B., in Pennsylvania is the congressional race. This is a special election, Democrat against Republican, Critz versus Burns for the late Jack Murtha's seat. How important is this race for the trend line?

STODDARD: So many elections tonight will test the power of the Tea Party, Barack Obama's political influence, the establishment in both parties, labor.

But in Pennsylvania 12 it's really a petri dish for control of the House this fall. Democrats are hoping in this conservative district where the labor is fighting very hard on behalf of Mark Critz that they can convince the voters in this district who voted strongly for John McCain and not for Barack Obama to vote for a long-time staffer of former Congressman John Murtha.

They think if they keep this from Republican control they'll have much fewer losses in the fall, a better year than they think they're going to have now, and that this is really going to be the indicator in Pennsylvania 12.

BAIER: Polls close at 7:00 in Kentucky, Charles, and the big race there is on the Republican side. The Democratic Senate side primary is also interesting, but on the Republican side you see Rand Paul, an eye doctor and once considered a long shot against the Secretary of State Trey Grayson. Rand Paul had a big surge coming into Election Day largely because of the Tea Party. What about that?

CHARLES KRAUTHAMMER, SYNDICATED COLUMNIST: I think that is the most amazing phenomenon of the day. He came literally out of nowhere. And when you compare him, politically he's not exactly like his father, Ron Paul. But Ron Paul when he ran for the presidency in 2008 was a bit of a joke. He was way out there.

It tells you how much our country has changed in two years that that kind of libertarianism was considered kind of kooky at the time, and now his son who is less libertarian, more sort of centrist, but still he is really challenging the Republican establishment, Mitch McConnell is supporting his opponent and it looks as if Paul has a really substantial lead.

This has been, I think, the amazing story of the last year. Look, the Tea Party, which is behind Paul, barely existed a year ago, and look what it's done. It helped elect a Republican to take the Kennedy seat in Massachusetts, it defeated a three-term Republican incumbent in Utah. Now it looks as if it may at least nominate a semi-libertarian in Kentucky, and in the race that you mentioned, the Murtha seat, a Republican candidate in a seat that has been held by Democrats for 38 years has a pretty good shot, and he is backed by the same energy in the Tea Party.

This is I think a tribute to how radical is the Obama agenda, the spontaneous reaction to overreach, the $1 trillion stimulus, the health care takeover, and cap-and-trade, all of that at the beginning of a term. This is an amazing, spontaneous phenomenon, and we'll see the effects tonight.

BAIER: Many polls close in Kentucky at 6:00 and the rest of them, the state split at 7:00. So we could have a call sometime after 7:00 in Kentucky in both of those races.

Quickly on two other issues, listen to Richard Blumenthal in Connecticut today.

(BEGIN VIDEO CLIP)

CONNECTICUT ATTORNEY GENERAL AND SENATORIAL CANDIDATE RICHARD BLUMENTHAL: Now on a few occasions I have misspoken about my service. And I regret that, and I take full responsibility. I will not allow anyone to take a few misplaced words and impugn my record of service to our country.

(END VIDEO CLIP)

BAIER: He's speaking out about a front page New York Times story in which he said numerous times he was in Vietnam. How big of a deal is this, A.B., for Blumenthal?

STODDARD: I really think he is finished. When he stands there and says he won't allow a few occasions where he misrepresented his service as Vietnam veteran to impugn his actual record, it's impugned his credibility and his legitimacy as a candidate. I think his candidacy is finished, I can't imagine he recovers from this.

BAIER: In the Democratic race in Connecticut. Indiana, Representative Souder resigning this week because of an extramarital affair, saying it'll be effective Friday.

HAYES: And it will be interesting to see, to pick up on what Charles said about the Tea Parties. One of the people most prominently mentioned as a potential replacement for the seat is Marlin Stutzman, who ran as a Tea Party candidate in the primary against Dan Coats, lost but had a very respectable showing, in part because of the voter intensity and the Tea Party excitement that are backing these kind of conservatives.