No, if anything you're defeating your argument. Remember back to the heady-days of 2003 when "everyone knew" that Howard Dean already had the keys to the Oval Office in his back pocket? He was vehemently anti-war, anti-business, anti-tax cuts, pro-abortion, etc., and he was the pick of every pundit and a big majority of Democrats in every poll. But when people actually went to the polls and had to throw the lever, they threw it for someone else. I think it's one thing for a politician to lose popularity in a regular slide, but for someone to be way ahead as the front runner and have most people just not vote for him, that's pretty unique. So why did it happen? This guy was the poster child for everything Democrats loved, but couldn't get any votes.
I think it's because of the "X" factor, with "X" being defined as (stated unscientifically) "there's just something about that guy that worries me." It was easier to quantify the "X" factor after the "I Have A Scream" speech, but what about all the primaries that he lost before that. What was it that turned people off at the last second? I know that for my parents it was after they heard that Dean's wife is Jewish (my parents don't like Jews) and nothing more than that. They supported every position Dean took, but wouldn't vote for him because of something as trivial as the religion of his wife. So what else was there? I think there were issues of trust involved, and I also think a larger percentage of Dems supported the war in Iraq than polls were showing, but only the folks who didn't vote for him know for sure.
So... what will be Hillary's "X" factor? I think that her willingness to stay in a bad relationship for reasons of personal gain and political power, just won't sit well with a lot of people. It shows a character flaw, and people notice those even when they don't realize they're noticing them. That's, I think, why people could say they would vote for Dean during a poll, but when it came time to pull the lever they decided "there's just something about that guy that worries me." I don't think that her marriage be a direct political issue, but it will certainly play a role in developing that "X" factor.