ABORTION: Favors abortion rights.

AFGHANISTAN: Add about 7,000 reinforcements from Iraq; threatened unilateral attacks on high-value targets in Pakistan "if Pakistan cannot or will not act."

CAMPAIGN FINANCE: Using private money after proposing to accept public financing if GOP nominee does, too; refuses money from federal lobbyists.

CUBA: Ease restrictions on family-related travel, money sent to Cuban Americans' families in Cuba. Open to meeting Raul Castro without preconditions. Ease trade embargo after "meaningful democratic change."

DEATH PENALTY: Supports for some crimes; wrote Illinois bill mandating videotaping of interrogations and confessions in capital cases and sought other changes.

EDUCATION: Encourage, not mandate, universal pre-kindergarten; partially tie teacher raises to test scores; overhaul No Child Left Behind; be less punitive toward failing schools; tax credit of up to $4,000 for college students who perform 100 hours of community service a year, paid for by ending corporate tax deductions for CEO pay and delaying moon and Mars missions.

ENERGY: More offshore drilling OK, but not in ANWR; proposes windfall-profits tax on largest oil companies, energy rebate of up to $1,000; opposed gas-tax holiday; open to tapping Strategic Petroleum Reserve.

GAY MARRIAGE: Opposes constitutional ban; supports civil unions; states decide about marriage.

GLOBAL WARMING: Ten-year, $150 billion program; produce "climate friendly" energy, require businesses to bid competitively for right to pollute; cut emissions 80 percent by 2050; joined McCain in sponsoring bill that would set mandatory caps on emissions; favors tougher fuel-efficiency standards.

GUN CONTROL: Voted to leave gun-makers and dealers open to suit; in Illinois, backed semiautomatic-weapons ban and generally tighter firearm restrictions.

HEALTH CARE: Mandatory coverage for children; no mandate for adults, but require employers to share costs of insuring workers and offer coverage similar to that in plan for federal employees; tax wealthier families more to pay estimated $65 billion-a-year cost.

HOUSING: $20 billion plan with tax credit for "struggling homeowners," scoring system for comparing mortgages, fund for mortgage-fraud victims, new penalties for fraud, aid to states and cities stung by crisis.

IMMIGRATION: Voted for 2006 bill that would have allowed illegal immigrants to stay in U.S. and gain residency after learning English, paying fines and back taxes and clearing background check; voted for fence.

IRAN: Backed off initial statement that he would meet Ahmadinejad without preconditions; says direct diplomacy with Iranian leaders would help U.S. seek tougher international sanctions; says he would intensify diplomacy before Israel feels need to take military action.

IRAQ: Opposed war, troop increase; voted against major military spending bill in May 2007; favors total withdrawal of combat troops in 16 months.

SOCIAL SECURITY: Would expand payroll tax to income exceeding $250,000 (tax now collected on up to $102,000); rules out raising retirement age.

STEM-CELL RESEARCH: Relax federal restrictions on financing of embryonic stem-cell research.

TAXES: Raise income, capital-gains and dividend taxes on wealthiest; raise corporate taxes; $80 billion in breaks mainly for poor and elderly; no tax filing for older workers making less than $50,000; mortgage-interest credit for lower-income homeowners who do not take mortgage deduction because they do not itemize.

TRADE: Strengthen NAFTA labor, environmental standards; in 2004, favored enforcement of deals.

His high-school basketball nickname at Punahou School in Hawaii was "O'Bomber."

As a child in Indonesia, he was introduced to snake meat and roasted grasshopper.

His maternal grandmother was a "Rosie the Riveter" at a Boeing plant in Wichita, Kan., during World War II.

He carries good-luck charms, including a gambler's lucky chit, a tiny Madonna and child, and a bracelet belonging to a soldier deployed in Iraq.

His favorite films include "Casablanca," "Godfather" movies, "Lawrence of Arabia" and "One Flew Over the Cuckoo's Nest."

How Joe Biden differs

IRAQ WAR: Voted to authorize military force before invasion.

CUBA: Supports continued economic sanctions.

DARFUR: One of the few senators to advocate use of U.S. troops to quell violence there.

CAMPAIGN FINANCE: Unlike Obama, accepts contributions from PACs.

ABORTION: Opposes abortion rights; has voted for restrictions permissible under Roe v. Wade and says he would seek to overturn it; would not seek constitutional amendment to ban abortion.

AFGHANISTAN: Favors unspecified boost in U.S. forces.

CAMPAIGN FINANCE: Co-author of McCain-Feingold campaign-finance law; running general campaign with public money and within spending limits, after turning down federal matching funds in primary so he could spend more; accepts contributions from lobbyists.

CUBA: Ease restrictions if U.S. is "confident that the transition to a free and open democracy is being made."

DEATH PENALTY: Has supported expansion of federal death penalty and limits on appeals.

EDUCATION: Favors parental choice of schools, including vouchers for private schools when approved locally, and right of parents to choose home schooling; increase money for community-college education.

ENERGY: Favors increased offshore drilling and federal money to help build 45 nuclear-power reactors by 2030; opposes drilling in ANWR; proposed suspension of 18-cent-a-gallon federal gasoline tax.

GAY MARRIAGE: Opposes constitutional amendment to ban it; says same-sex couples should be allowed to enter into legal agreements for insurance and similar benefits, and states should decide about marriage; supports federal Defense of Marriage Act, which denies federal recognition of same-sex marriages and allows states to refuse to recognize such marriages.

GLOBAL WARMING: Led Senate effort to cap greenhouse-gas emissions; favors tougher fuel-efficiency standards; favors plan that would cut greenhouse-gas emissions by 60 percent by 2050.

GUN CONTROL: Voted against ban on assault-type weapons but favors background checks at gun shows; voted to shield gun-makers and dealers from civil suits.

HEALTH CARE: No mandate for universal coverage; favors replacing tax exemption on employer-provided insurance with $2,500 annual tax credit to individuals, and $5,000 to families, to purchase coverage, in hopes that people would purchase insurance and free companies from the heavy cost of providing coverage. The theory: Employees would flock to the open market, where insurance companies would have to become more competitive to win their business.

HOUSING: Open to helping homeowners facing foreclosure if they are "legitimate borrowers" and not speculators.

IMMIGRATION: Sponsored 2006 bill that would have allowed illegal immigrants to stay in U.S., work and apply to become legal residents after learning English, paying fines and back taxes and clearing background check; now says he would secure border first; supports fence.

IRAN: Favors tougher sanctions; opposes direct high-level talks with Ahmadinejad.

IRAQ: Opposes troop withdrawal timetable; supported decision to go to war, but was early critic of Bush administration strategy; key backer of troop increase; willing to have permanent U.S. peacekeeping forces in Iraq.

SOCIAL SECURITY: "Nothing's off the table."

STEM-CELL RESEARCH: Supports relaxing federal restrictions on financing of embryonic stem-cell research.

TAXES: Pledged not to raise taxes, then equivocated, saying nothing can be ruled out in negotiating compromises to keep Social Security solvent; twice opposed Bush's tax cuts, at first because he said they were tilted to the wealthiest and again because of unknown costs of Iraq war; now says tax cuts, which expire in 2010, should be permanent; proposes cutting corporate tax rate to 25 percent; promises balanced budget in first term.

TRADE: Free-trade advocate.

His pet peeve is politicians who talk too much. (He admits he's guilty, too, sometimes.)

He was addicted to the TV show "24."

His wife, in Bangladesh on a charity mission, didn't talk to McCain before bringing home an adopted girl.

He's serious about barbecuing and likes to deep-fry turkeys in peanut oil.

He doesn't e-mail or surf the Web. He likes to read the newspaper in print. He's attached to his cellphone.

His favorite movies include "It's a Mad, Mad, Mad, Mad World," "Casablanca," and "Viva Zapata!"

How Sarah Palin differs

ENERGY: Favors drilling in Arctic National Wildlife Refuge.

EDUCATION: Favors teaching creationism alongside evolution.

ABORTION: Favors total ban unless a doctor certifies that a mother's life would end if the pregnancy continued.

GLOBAL WARMING: Has said she does not believe man is contributing factor.