*****SPOILER ALERT*****
I have a bunch of different tricks that got me to the end without a major crisis. Maintained about 65% of the vote right up until the end, before going hog wild. It didn't seem possible to actually get unemployment under control (i.e. below 15%), but if you keep retirees & private workers (the two largest groups) happy you're not gonna get thrown out. Basically I cut unemployment benefits in half right off the bat, and cut public worker compensation to the bare minimum immediately. A third of your public workers will disappear immediately, making their opinion of you meaningless. You then spend the savings on reduced VAT tax and increased retirement benefits. Reduced VAT (keep it around 18%, maybe a point or two higher if inflation is high) will encourage investment and consumption throughout the game, especially combined with low inflation. Income tax around 18% is good, to keep people happy, but you want to actually increase this when you see private worker compensation going through the roof. If you don't increase it (and reap the profits!), what you'll find is private worker compensation will get so high that the labor market overheats and kills hiring - the unemployment rate will skyrocket not just in spite of, but *because of* your low-tax policy. I kept retiree income at $1000 all the while - a level that fosters consumption and makes retirees happy due to "high income" but won't break the bank. Doing all of this, you'll just about break even on your budget surplus/deficit. Never do anything specifically because there's a deficit or a surplus - that'll get you annihilated. Leave your surplus alone and pocket it, and suffer through your deficit, and in the end you may do better than my 41% debt-to-GDP ratio. I took my 41% debt-to-GDP and went on a little spending spree in the last 6 or 7 turns by boosting retiree and unemployment income a hundred bucks every turn or two (although keeping below private worker levels), while cutting VAT taxes a point or two every turn. The extra growth means that the lower tax rates are a wash in the short-term, so your debt-to-GDP won't increase significantly - you should be around 65% to 70% approval rating with 40 to 42% debt-to-GDP. Unemployment will have fallen to around 4 or 5 percent, although it's not sustainable because it's dependent on the artificially strong growth rate. Then in the last couple of turns, figure what percentage of your GDP you can spend to get up to 50% debt-to-GDP while conferring the greatest possible short-term economic advantage, and do a small fraction of that on the second to last turn, and then blow all the remaining cash on the last turn. Wildly lower taxes and drastically higher spending. Inflation and investment rates be damned at this point. Election day arrives and voila, 90% approval!
*****End Spoiler alert*****
If anyone has a way to balance all the competing priorities, I'd love to hear it. Also, if you made it through with a lower debt-to-GDP at the end-game, massive GDP, or a higher approval rating at the end, please share.