Former Sen. Larry Pressler (R-S.D.), who was the first Vietnam veteran to serve in the United States Senate, is the latest Republican to back Sen. Barack Obama’s presidential campaign, Politico learned Sunday.

Pressler, who said that in addition to casting an absentee ballot for Obama he’d donated $500 to the Illinois senator’s campaign, cited the Democrat’s response to the financial crisis as the primary reason for his decision.

Pressler, who admitted that he’d never voted for a Democratic presidential candidate in his life before Obama, said it was difficult to vote against a Republican he served with in the Senate, but emphasized how impressed he’s been with Obama’s team of economic advisors, and added that McCain’s “handling of the financial crisis made me feel nervous.”

Pressler joins Colin Powell, William Weld, Arne Carlson, Charles Fried, and other notable Republicans who’ve recently announced their support for Obama.

But Pressler’s explanation for why he dumped McCain for Obama is the part that stood out for me. For weeks, the pundits have noted that the financial crisis has seriously undermined the McCain campaign. That’s true, but it overlooks why — McCain has handled the crisis really badly. It’s not enough to simply note that a focus on the economy is necessarily good news for Obama; McCain had a chance to deal with this crisis effectively and he blew it.

As Obama recently told Rolling Stone, in recent years, McCain has confronted two major crises. “One is the war in Iraq, and the other is what’s happened just over the last three and a half weeks on Wall Street. In both instances, what you’ve seen is John McCain being impulsive, not getting all the information that he needs, surrounding himself with people who are predisposed to agreeing with him. And as a consequence, I think he’s made bad judgments.”

A surprising number of Republicans have apparently reached the same conclusion.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.