That's what the facts say...
Please link to a reliable source. Seriously you love doing this don't you? I'm good at research and statistics, but I can't seem to find anything relevant to your accusation.
While I assume you're referring to the few cabinet nominees that had some tax problems; small liens against businesses, some personal unpaid taxes, and so on, all of which does not constitute cheating on your taxes (which infers intent to deceive). There was no deception present, simply a lack of paying, either through not knowing about it ( Solis' husband, owed about $6000 in taxes, which he paid, he stated he hadn't received a notification, as soon as it popped up he did take care of it). The daschle case was a bit stupid on his behalf, of course I don't fail to realize that not everyone in the democratic side of things is perfect and some are down right wrong in their actions, I do not feel this reflects badly on the entire party since it is a very minor constituency.
Now if we want to gauge things in terms of republicans, we can make a prime example of Sam Wyly,
http://www.nytimes.com/2006/08/01/business/worldbusiness/01iht-tax.2356752.html?_r=1 "The report also dissects deals by the Wyly brothers of Texas, showing how they made at least $190 million through stock option exercises offshore but have yet to pay taxes on most of the money." , They also were accused by the SEC of cheating their shareholders out of a good chunk of money in 1979. Back to taxes, $190 million means a whole lot more than a likely accidental $6300 back tax snafu by THE HUSBAND of a cabinet candidate.