Things that might happen

1. Despite clear majority support for Barack Obama, Hillary Clinton clinches the Democratic nomination by receiving barely enough superdelegate votes. Disgusted voters reject the ticket as just another backroom deal, and Obama and Ralph Nader form a third party.
2. A national security crisis in September, causing much death and destruction, is used to justify another invasion and a deepening of the current conflict. Conspiracy theories are rampant but are not reported in the mainstream media.
3. Election of John McCain on a "Patriot" platform, with Dick Cheney as Vice President, who install a "War Cabinet" and reinstitute the draft by executive order. Bush effectively steps aside in November, and is hailed as a "lover of peace" and "defender of freedom." Inauguration day is marked by rioting and violence, and scores of police and demonstrators are injured or killed nationwide.
4. The pope asks Catholics worldwide to stand down for peace, and he is assassinated. A logistical miscalculation causes Israel to blame the assassination on "Islamic Terrorists" before it has actually occurred.
5. Widespread civil rights abuses in the U.S. and abroad, flagrant disregard or suspension of rights guaranteed by the first, second, fourth, and sixth amendments, and international outcry against military actions. The Supreme Court remains silent.
6. A moratorium on immigration and foreign nationals sent home, leading to a domestic labor crisis and hyper-expensive groceries. Double-digit inflation.
7. Imported oil reaches $300 per barrel.
8. Mexico becomes the 51st state, providing cheap oil, cheap mineral resources, cheap labor, cheap manufacturing, and more young people to draft into service. Fortune-500 companies invest heavily and are richly rewarded. GMC and Chrysler move production to Mexico, Ford bankrupts, and Duesenberg reappears. Canadian newspapers decry "Fortress America" mentality, and are vilified by conservative U.S. media. Calls from the far right to annex Yukon Territory.
9. All domestic oil reserves are called into production, including new drilling in National Parks and Forests, and eminent domain provides new rights-of-way for miners and loggers.
10. E.U. and Russia enter trade agreement with China, effectively ending U.S. world economic hegemony.
11. China sells its treasury bills, further depressing the U.S. dollar.
12. Large-scale collapse of credit and banking system, exacerbated by a poorly-managed F.D.I.C. and its politically-appointed leadership. Price of Gold reaches all-time high.
13. The U.S. enters a second "great depression."
14. Automobiles become prohibitively expensive to maintain, and people can no longer afford to live in the suburbs.
15. People ride bicycles more and more.
16. Bike mechanics are in high demand and bike shop owners get rich.