Half right is almost the whole problem
Minnesota's last Governor, Jesse Ventura, was a surprise to many on both sides of the political aisle. I've maintained for some time that his success was not purely based on celebrity and curiosity. That much may be able to open a door, but that much alone will not get someone invited in through that door.
When I first heard Ventura was running my reaction was on the order of, "You're kidding, right?" But I heard a few radio interviews and at least parts of a couple debates. Ventura was the guy making more sense than the DLFer (Democrat) and the Republican who were running for the same office.
There were a few things Jesse did that made him stand out, never mind his past in entertainment. One was that he was outspoken and consistent. Someone might not like what he said, but he didn't try to be whatever his current audience wanted to hear. Another was that when he didn't know something, or didn't know enough about something to make a reasonable comment on it, he said so. The stunned silence when he first did this is still memorable. No BSing an answer, but a simple admission that he didn't know - and would be rectifying that so he could give a real answer later. Yet another was that he refused to be baited into making promises that he knew he could not keep or would likely be unable to keep. More than once he asked reporters what part of "no" they did not understand.
All that was good, but there was something else. Something the neither the DFL/Democrats nor the Republicans seem to have completely caught on to. Other parties, even the Independence party that formed when Ventura left the Reform party, haven't quite grasped it either. Perhaps the Libertarians have figured it out, but they have another problem to work out.
It's this: Jesse Ventura had both halves of what is desirable. The Republicans have one half, or try to. They claim that less government is better and the hand on your wallet should be yours, not the government's. The DFL/Democrats have one half or try to. They claim that government should not try to legislate morality and whoever is in your bedroom or such is your business and not government's. Each group has half of the message: the best government is the one which interferes with you minimally, to paraphrase Thoreau. (The Libertarians have figured this out, but have carried it to what is too extreme for most people.)
The two major parties both miss the boat by being only half-right, when they're right at all. Either one could easily win the hearts and minds of many of the undecided and wavering by having the full message. That would require jettisoning part of their current base, however, so don't hold your breath.
The Democrats/DFL have a faction that seems intent on spending more money to solve problems by methods that have failed to work. The idea that equality of result can be guaranteed by government is the theme of this faction. Anyone who points out that this doesn't work gets painted as being heartless, even if all that is said is that maybe trying something different might get better results than doing the same old things over and over.
The Republicans have a faction intent on foisting their version of religion or morality on everyone, whether those others subscribe to those beliefs or not. Those who point out that that isn't the American Way, to the point of being forbidden in the Bill of Rights, get painted as evil and the downfall of our alleged civilization.
Both parties would be better off if they could just get past those factions and get on with the Jeffersonian ideals to which they both have claimed to hold. As it is, the primaries seem to allow each faction to control the party and presidential nominee with the result that neither party has a candidate which most people would really like to vote for. Instead, most people take a look at each party's nominee and vote against the most objectionable one that they see.
Even if one of the major parties managed to shake themselves of their extreme factions, they'd have a rough go for a while. There is a history and inertia and it would be some time before people would be willing to believe that the change was real and not just so much more election-year lip service. This is why even though a Republican House and Senate and White House have been spending more, the Democrats still have to fight off their long, sorry reputation as tax-and-spenders and can't simply claim the budget hawk position once (and still, to some degree) used by the Republicans. The Democrat's free-spending reputation precedes them, so even if they actually started acting like budget hawks, it would be some time before it was considered real. Likewise, even if the Republicans jettisoned the "religious right" this very instant, they'd still have a fight to get people to believe it was for real.