Obama wants to create jobs by keeping taxes low for everybody but the wealthiest and with public-works spending, clean energy projects and targeted tax breaks to businesses. Romney proposes further cuts in tax rates for all income levels; he'd also slash corporate rates, reduce regulations and encourage oil production.
Education ranks second only to the economy in issues important to Americans. Yet the U.S. lags globally in educating its children. And higher education costs are leaving students saddled with debt or unable to afford college at all.
State budget cuts have meant teacher layoffs and larger class sizes. Colleges have had to make do with less. It all trickles down to the kids in the classroom.
Although Washington contributes a small fraction of education money, it influences teacher quality, accessibility and more. For example, to be freed from provisions of the No Child Left Behind law, states had to develop federally approved reforms.
Romney wants more state and local control over education. But he supports some of Obama's proposals, notably charter schools and teacher evaluations. So, look for them to be there whoever wins the White House.
European economic crisis:
Europe is struggling to control a debt crisis, save the euro currency and stop a repeat of the 2008 financial crisis that sent the world into recession.
Europe's troubles are the No. 1 threat to the U.S. economy. The biggest fear is that the 17-country eurozone will split, causing a financial crisis that will spread across the Atlantic, freeze credit and send the U.S. economy back into recession.
Neither Obama nor Romney has offered plans for Europe. The U.S. government lacks the cash and the will to rescue European countries struggling with huge government debts.
Obama has urged Europe to act more decisively. Romney warns that the United States will face its own day of reckoning if it can't reduce the federal debt. Many economists call for eurozone countries to assume joint responsibility for the weakest countries' debts through eurobonds; Germany has balked at the idea.
Both sides of the gay marriage debate agree on this much: The issue defines what sort of nation America will be.
Half a dozen states and the District of Columbia have made history by legalizing it, but it's prohibited elsewhere and 30 states have placed bans in their constitutions.
Obama supports legal recognition of same-sex marriage, as a matter decided by states. Romney says same-sex marriage should be banned with a constitutional amendment.
The debate divides the public down the middle, according to recent polls, and stirs up passion on both sides.
In November, four states have gay-marriage measures on their ballots. In Minnesota, the vote is whether to ban gay marriage in the state constitution. Voters in Maine, Maryland and Washington state are voting on whether to legalize gay marriage.
Thus far, foes of gay marriage have prevailed in all 32 states where the issue reached the ballot.
Gun violence has been splayed across front pages with alarming frequency lately: the movie theater killings in Colorado, the Sikh temple shootings in Wisconsin, the gunfire outside the Empire State Building and more. Guns are used in two-thirds of homicides, according to the FBI. But the murder rate is less than half what it was two decades ago.
Neither Obama nor Romney has had much to say about guns during the campaign. Obama hasn't pushed gun control measures as president; Romney says new gun laws aren't needed.
It's getting harder to argue that stricter gun laws are needed when violent crime has been decreasing without them.
But the next president may well fill at least one Supreme Court seat, and the court is narrowly divided on gun control. An Obama appointee could be expected to be friendlier to gun controls than would a Romney nominee.