This is a rush transcript from "Hannity," April 28, 2009. This copy may not be in its final form and may be updated.

SEAN HANNITY, HOST: And in "Your America," tonight, now earlier today Arlen Specter made the announcement that many thought was long overdue, that he is leaving the Republican Party after 28 years to become a Democrat. Now the senator made the decision largely to avoid another challenge in the primaries by my next guest. And we're joined by former Pennsylvania Congressman Pat Toomey.

Congressman, good to see you.

PATRICK TOOMEY, FMR PENN. CONGRESSMAN: Great to be with you, Sean. Thanks for having me.

HANNITY: Well, I think I found your first campaign commercial, running against Arlen Specter, assuming you win the primary. And that's Arlen Specter, he wasn't happy when Jim Jeffords left and become a Democrat and he said "that kind of instability is not good for the governance of the country or the Senate." Is that something you'd use in a campaign ad?

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TOOMEY: Well, absolutely and he also spent the last several weeks and months crisscrossing Pennsylvania promising that he absolutely would not leave the Republican Party and insisting that it was a very good idea to have some Republican ability to oppose a Democrat agenda. We've discovered that all he really cares about is his own political future. I don't think that's going to wash with Pennsylvania voters.

HANNITY: Well, and he was saying this as recently as just two weeks ago, that is — and he went through this whole list that, you know, "the only thing standing between the Democrats and an avalanche are 41 Republican senators to filibuster." He said that.

He went on to say that the Democrats would have 40 — Republicans would have 40 and the Democrats would have 60 and they would control all mechanisms of government and he said, look, him being a Republican was a national asset.

So, clearly something's happened. Clearly he put his own self-interest above the interests of the people of Pennsylvania and the country. So, the question is how will the people of Pennsylvania respond, in your view?

TOOMEY: Well, you know, any way you look at this, this is a very serious act of betrayal. I mean, he's been, at least a nominally Republican for 30 years, taken Republican contributions, taken Republican support and then after, you know, right through last Friday, Sean, he was insisting that he wasn't going to switch parties and then we discovered that, well, we know what his word is worth now. I think Pennsylvania voters are going to ask themselves can we trust this guy about anything.

HANNITY: How will he do in a Democratic primary which is probably likely?

TOOMEY: I think it is likely. I think that's a good point and it's a big question because, you know, he's betrayed Democrats as well. You know, he joined up with organized labor and promised to support their bill to deny workers a secret ballot. Then when I announced I would likely be running against him he decided to switch his position. Today who knows where he is. But how can anybody be confident he will represent what he says he will? Clearly his record of duplicity underscores that he won't.

HANNITY: But, knowing the importance now that he could be that 60th vote, that filibuster-proof vote for the Democrats, but he did it anyway and we now learn that Joe Biden has met with him 14 times, the president called him moments after it was announced, today. So, do you think that there is a potential that Barack Obama and Joe Biden are offering or offered him something, some kind of support? Did he meet with Ed Rendell? These questions that you think need to be answered, was he promised anything?

TOOMEY: Oh, I think he was promised all kinds of political support. He was promised by Harry Reid a very senior position on the committees. I think he was promised many things and encouraged by the leadership of the Democrats to join their efforts and I understand he was quoted as saying to Barack Obama that, "I'm a loyal Democrat and I support your agenda." So, you know, I just think that kind of duplicity is going to go down really hard in Pennsylvania.

HANNITY: How do you go from, and I guess this is the question, how do you go from saying I'm a part of the Reagan revolution, where they cut taxes to stimulate the economy, he tried to lower lessen the scope and influence of government in our lives, had a strong national defense — how do you go from that to embracing the Castro brothers, Hugo Chavez, Daniel Ortega and calling America arrogant? How do you make that leap?

TOOMEY: Well, Sean, for Senator Specter, it's not much of a leap. You know, he says the Republican Party has gotten too conservative. The Republican Party was too conservative for Specter in 1980. He didn't like what Reagan stood for, he never has. So, he's always been a fish out of water. Now he's gone home to where his sort of ideological home is, but again, the duplicity along the way, I think, really undermines his credibility with voters.

HANNITY: Yeah, well, look, you were up, it was 51-30 in a potential primary runoff, now. Have you been doing any polling? What is his favorabilities in the state, do you know?

TOOMEY: I haven't done any recent polling, Sean. I do know that he is — well, let's face it, he knows, we all know that Arlen Specter is extremely unpopular amongst Republicans, but I think his support for all the bailouts, all the Wall Street bailouts, the car company bailouts, all the massive spending and the huge debt, the taxes that are, of course, coming along with that, I think that's going to put him out of step with a big majority of Pennsylvanians, including most independents and many Democrats.

HANNITY: Look, Pennsylvania's been one of these states Republicans keep thinking every election that they can come back and win. But is it always seems to be out of reach. Is it bluer than maybe you think? Is it a Democratic state?

TOOMEY: Sean, at the presidential level, it's true, we haven't done well, but at other levels we really have. You know, we've got a big Republican majority in the state Senate, we're only a few seats shy in the state House. Until recently, we've had two Republican senators although one has only been nominal.

No, you know, we've had a couple of tough elections cycles, but a message of ending the bailouts, limited government, fiscal discipline, personal freedom and personal responsibility, strong defense, that message resonates across, you know Reagan Democrats, Republicans, independents, across the board.

HANNITY: All right, we're going to be watching this race very closely. Congressman, thank you for being with us tonight, appreciate it.

TOOMEY: Thanks for having me, Sean.

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