Sen. Arlen Specter today made his Sunday show debut as a Democrat—and defended his party switch. The real reason behind his decision? Not just his bleak chances in a Pennsylvania Republican primary in 2010, he said. And not promises, from him or the Democrats: The party made no pledges to get him to switch sides, he said, and he, despite the rumors, did not vow to be a "loyal Democrat." A "critical factor" was his vote for Obama's $787 billion stimulus package. "I bucked the Republican line," he said. "And that created a schism. My approval rating dropped 30 points with Republicans as a result of that vote." After he became one of only three Republican senators to support the stimulus, Republicans "ostracized" Specter, he said. "I was sorry to disappoint many people; frankly, I was disappointed that the Republican Party did not want me as their candidate," he said. "But as a matter of principle I am becoming much more comfortable with the Democrats' approach."