The news folks will spend about 48 hours to tell this story, and then dump it. It's pure speculation on their part. So I sat and speculated upon this as well. My theory?
I think the Democrats had polling done three months ago that asked a couple of questions and felt good on making a big stand over immigration, and denying the wall construction money. Things were fine.
I think in the past week, they did another poll....asking additional questions. Then they hit the imaginary 'pit'.
If you went into the thirty states that President Trump won, I suspect there is a very high number of folks who were asked about supporting the Democratic position, and their response was that this shutdown could last weeks for them, and they didn't care.
Why this pro-shutdown feeling? I think the news media from 2008 to 2016, hyped the theme that shutdowns were 'OK'. And the public simply got used to it.
So just talking about a shutdown for ten days? Well....it no longer bothers people. On their list of the top hundred things to worry about....a ten day shutdown won't even make the list anymore.
I can remember the late 1970s when I joined the Air Force and this first threat of no budget came up, and being told that I wouldn't get a pay-check. I sat there, with a measly $500 in the bank and kinda wondered how many pay-days could I miss? Living in the barracks....I could cut myself down to $20 a week on expenses, but I couldn't imagine this going for more than two weeks before a bunch of folks were in serious financial trouble.
These days, the threat occurs so often....that guys put more to the side and prepare for each shutdown. But I don't think most Americans really care anymore.