Here's a dreadfully off the mark bit of analysis from Joe Klein on why Tommy Thompson dropped out of the race:

The other factor is that Thompson, much as he tried to pretend otherwise, simply wasn't as conservative as the Republican base. Unlike Ronald Reagan and George W. Bush (and now Mitt Romney), who act as if Washington, D.C. were the capital of France, Thompson actually believes in government and practiced his beliefs in a creative, humane but highly efficient way, especially when it came to welfare reform in the early 1990s. That seems a terrible liability for a GOP candidate these days.

I believe this is the first time I've ever seen anyone cite welfare reform as a "terrible liability" for a Republican. To the contrary, it's one of the most successful policy programs of the last few decades - forced into being by a Republican Congress over the stubborn opposition of Bill Clinton - and is viewed favorably by Republicans, which is why Thompson mentioned his role in its creation at every possible opportunity.

(Incidentally, Thompson also touted his involvement in the beginning of another "creative, humane and highly efficient" policy which Republicans love and Democrats despise: school choice. Milwaukee was among the first cities to begin a pilot program for vouchers.)

As for Thompson not being "conservative" enough for the Republican base, would Klein care to explain why Rudy Giuliani is maintaining a strong lead in the national polls, running second in Iowa and New Hampshire, and leading in South Carolina and Florida?

Truth be told, Tommy Thompson was plenty conservative enough for Republican voters; pro-life, pro-Second Amendment, against gay marriage, against amnesty for illegal immigrants, etc. (Scroll down this list of his positions to see for yourself). He's certainly more conservative than Giuliani, and more consistently conservative than Mitt Romney.

The problem, as everyone but Klein seems to recognize, is that while Thompson may have been an excellent four-term executive for the state of Wisconsin, he turned out to be a terrible national candidate. He bombed in the debates, and he made a couple of disastrous gaffes which made him seem out of his league.

Even in Iowa, where most people - including Thompson himself - thought his brand of retail politicking would pay dividends, Tommy failed to connect with and motivate Republican voters.